Anamorphic lens shootout. Pics.

[Alan Gouger]

I have a good assortment of anamorphic lens on hand and thought I would take advantage of the opportunity and compare them all side by side.

I used a Canon G3 for the pictures. The projector used was the Seleco 300 on an 8.5 foot wide Silverstar 235:1 screen.

Combined with my native 16x9 DLP the anamorphic lens optically results in a 235:1 ratio using the projectors full panel.

I used the cross hatch pattern and text from DisplayMate.

I used the test pattern to show overall focus of each lens.
Using the course cross hatch I shot the left and right side of the screen to show chromatic aberration of each lens.
To my surprise all the lens had this, some worse than others and all had this in a none uniform pattern, worse on one side of the screen verses the other.

Chromatic aberration looks like a mis converged CRT with red and blue lines showing on each white line making up the cross hatch.
While this is quit evident on the test patterns it was not visible watching normal movie material. You had to look for it.

The pictures did not turn out as bright and clear as I wanted but you can still make everything out.

[Alan Gouger]

http://gallery.avsforum.com/data/509/2Picture_020.jpg

Left to right.

1. Prismasonic H500. The H stands for horizontal.
Turning the knobs ( one for the left side of the image and one for the right) allows you to stretch the width of the image anywhere from a pass through mode to 235:1 or wider. There is also a H200 model. The 500 offers high quality optical coatings.

2. Prismasonic H1000. This lens is not shipping yet. It is a beta version. It will cost more than the H500. It offers better optics reducing the chromatic aberration.

3. Panamorph. This lens compresses the image in the vertical direction. It also has quality optical coatings.

4. Isco 2. This lens stretches the image in the horizontal plain and like the others contains high end optical coatings.

[Alan Gouger]

These images show each lens showing overall focus.
All are close but the Isco definitely has the edge.
Next was the Panamorph and then the Prismasonic lens. This was very evident viewing them in person but its something not as easy for the camera to capture.
I posted the pictures in the order from best focus to the softest. You can see each lens gets a little softer toward both ends of the screen.

Isco. The Isco is the only lens that zooms the image to a slightly larger size. Not evident in the picture but it also has some minor top/bottom pin cushion but its focus if razor sharp corner to corner compared to all the other lens.
http://gallery.avsforum.com/data/509/2Picture_017.jpg

Panamorph. This lens does very well also. It adds some keystone distortion as well as barrel distortion. Focus comes in second.
http://gallery.avsforum.com/data/509/2Picture_017.jpg

Prismasonic H1000. The prismasonic lens do not have any geometry distortion, they are the best of all the lens in this regard.
Focus is not as sharp, always off a little on one side verses the other but over all a good performer.
http://gallery.avsforum.com/data/509/2Picture_013.jpg

Prismasonic H500. Same as the 1000 but the 1000 is a little sharper.
http://gallery.avsforum.com/data/506/2Picture_0041.jpg

[Alan Gouger]

This post is made of images taken of both the left and right of the screen so you
can compare the differences in chromatic aberration between each lens.

The first image of every group will be the left side of the screen with the second being the right.

Isco.
http://gallery.avsforum.com/data/509/2Picture_018.jpg
http://gallery.avsforum.com/data/509/2Picture_019.jpg

Prismasonic H1000
http://gallery.avsforum.com/data/506/2Picture_00511.jpg
H500http://gallery.avsforum.com/data/506/2Picture_0071.jpg


Panamorph
http://gallery.avsforum.com/data/509/2Picture_0141.jpg
http://gallery.avsforum.com/data/509/2Picture_015.jpg

Prismasonic H500
http://gallery.avsforum.com/data/509/2Picture_011.jpg
http://gallery.avsforum.com/data/509/2Picture_0101.jpg

[Alan Gouger]

The Panamorph was the most uniform as far as chromatic aberration with the Prismasonic H1000 coming in tied with the Isco.

The isco is the clear winner as far as brightness and sharpness.
The Prismasonic H1000 and the Panamorph are tied for second leaving the prismasonic 500 last but for the money the H500 does very well.

I hope these pictures help.
Its nice to have a variety of anamorphic lens on the market at different price levels and designs that fit different applications allowing something for everyone regardless of your needs and budget:)

[Michael Grant]

Wow, this is excellent. Thanks Alan!
What was the throw distance used for the test? I've heard that longer throws tend to reduce the geometric distortion.

[Alan Gouger]

Thanks Michael.

My projector is ceiling mounted 18.5 feet from the screen. It shines through a porthole.
The porthole is large enough that the bottom serves as a self to set each lens (one at a time of course)
It worked out well.

I've heard that longer throws tend to reduce the geometric distortion.

You bring up a good point I forgot to mention. You are correct.
The Isco and the Panamorph both offer a large enough aperture to accommodate any long to mid throw projector but they both have pincushion or barrel distortion regardless.
The Prismasonic lens has a limiting aperture and unfortunately will only work with long throw projectors zoomed to the smallest image size at that but these lens had no geometry distortion at all.


My Seleco is mounted as far back as possible and is zoomed to its smallest max position. This is important to know and I should have noted this to the above post somewhere.

[sfogg]

Alan,

Thanks, the pictures look good. With the focus on the Prismasonics being uneven to one side have you tried rotating the whole unit slightly side to side and then readjusting them? That might help.

On the Panamorph since it is changing the picture vertically wouldn't any CA more likely to be on the top and bottom of the picture? All the other lens in this comparison are stretching horizontally.

Shawn

[Cain]

Very interesting Alan.

Thank you !!

-- Cain

[Alan Gouger]

Hi Shawn

I moved the Prismasonic lens in all directions including in and out from the left and right but nothing has an effect on the focus.

The Panamorph had even CA over the entire screen. It looked better than I remembered and was the best of all the lens. Side to side & top to bottom were all the same.

[Bytehoven]

Nice review Alan.

Which model Panamorph did you have?

It looks a little different from the HT1000 style Panamorph lens. Is that the new lower priced U10 Panamorph lens?

Thanks again for the comparison.

RJ
...

[Alan Gouger]

RJ

It is the HT1000 but with a different mount.

[Charles R]

Alan,

Great work... from your results and or experience do you feel it's worthwhile to add one of these lens to a 4x3 projector for displaying 16x9 (in most cases)?

[Ursa]

I'd be curious as to how the new "consumer grade" panamorph performs compared to the one you tested. With both keystone and barrel distortion, it may be a bit of letdown for folks joining the power buy.

Later,
Bill

[sfogg]

"The Panamorph had even CA over the entire screen. It looked better than I remembered and was the best of all the lens. Side to side & top to bottom were all the same."

Thanks, that the Panamorph had the best CA of the group doesn't suprise me since it was the only one of the group that makes the picture smaller. All the rest are expanding the picture.

BTW, I got a little bit of a chance to try the H500 this morning. I did see some ca on the right side when the lens was doing about 1.33 expansion to go from 4x3 to 16x9. It was obvious on grid patterns when standing up near the screen but moving back to the seating position (just a little over 1 screen width away) it was much less visable on the grids. My panels (Dila) aren't perfectly aligned either which might have been masking it slightly.

When watching film/video the only place I really saw it from the seating position was on the hard edge of the picture. An 1/8" of masking on the edges would hide it.

When I pushed the lens out to 1.5 expansion (1.33 AR to about 2.0AR) it did get worse and could be seen on things like white DVD text menus from the seating position. 1.5 expansion was as far as the lens would go.

This was all with a really quick temporary setup. With everything better squared up it might be a little bit better.

What was also nice was I was able to go through the full zoom of the Dila without running out of aperature size on the H500. So I will be able to use the lens to go from 1.33 to 1.78(or a little more). Then for constant height on 2.35 material use the zoom to get me the rest of the way there.

Shawn

[MrWigggles]

Thanks Alan,

As a point of reference I could never completely get rid of the chromatic aberation of my ISCO II lens when I had it with my LT150 which has about a 1.6:1 throw ratio. The LT150 doesn't have a zoom either

Keep the throw ratios long, 2.0:1+, before adding the ISCO (1.5:1+ after)and you'll be in really good shape.

-Mr. Wigggles

[Alan Gouger]

Charles

I cannot answer that for everyone, its personal taste.
Using one does soften the image a little. The additional light output gained is marginal to the eye but I like the smothness it adds.

Bill

I think it uses the same lens so the quality will be up to the standards of the current model.

Shawn

The prismasonic is still my favorit because of the adjustment. I find it the most flexible.




by wigggles, Keep the throw ratios long, 2.0:1+, before adding the ISCO (1.5:1+ after)and you'll be in really good shape.

Mr. Wigggles

Good advise for anyone wanting to use this lens. I think your advise also benifits anyone using an anamorphic lens regardless what brand.

[Brandon B]

Thanks Alan. Very good information.

BB

[Morbius]

Originally posted by sfogg
"The Panamorph had even CA over the entire screen. It looked better than I remembered and was the best of all the lens. Side to side & top to bottom were all the same."

Thanks, that the Panamorph had the best CA of the group doesn't suprise me since it was the only one of the group that makes the picture smaller. All the rest are expanding the picture.

Shawn,

The fact that the Panamorph makes the image smaller doesn't explain the quality of
the chromatic aberration.

After all, even though the Panamorph itself makes the image smaller - the rest of the
optics will expand it so that the image has the correct size on the screen.

The overall magnification, to first order, is identical among the different lenses - the
difference is which component is doing the magnification. Because the ISCO does
a certain degree of magnification itself - the rest of the optics chain does less
magnification.

The fact that the Panamorph compresses the image - means that other lenses in the
optics change must compensate for that - so that the overall magnification is the same,
and the picture fits the screen - the same as the other anamorphic lenses.

[sfogg]

"- so that the overall magnification is the same, and the picture fits the screen - the same as the other anamorphic lenses."

Overall magnification of the projector and the lens is irrelevant.

We are talking about what each anamorphic lens alone is doing. The Panamorph is shrinking the image smaller vertically. The other lenes are expanding the picture wider horizontally. They are just about complete opposites of each other.

It isn't suprising that the color seperation of the panamorph is smaller since it is working in the opposite direction of the other lenses. If the Panamorph has 'ca' it is reduced by the very action of its compressing the image passing through it. It is concentrating the light passing through it.

The other lenes are making the picture larger, IOW expanding the light passing through it. That expansion will make color separation more obvious.

Shawn

[David Wallis]

It isn't suprising that the color seperation of the panamorph is smaller since it is working in the opposite direction of the other lenses.The other lenes are making the picture larger, IOW expanding the light passing through it. That expansion will make color separation more obvious.
That is a totally false assumption. It shows clear confusion of the principles of how it works.

No matter what type of anamorphic lens (expand / compress) you use with your projector, you still have to fill the actual chosen screen size and you are still at the projectors fixed resolution.

Not counting design issues or optics superiority (ie: all things being even except method e.g. expand / compress). When using a different 1.78:1 anamorphic lens, the light output is going to be the same per inch of screen, the pixels per inch are exactly the same when using the same projector on the same sized screen, . The only main difference is throw distance to screen.

DavidW

[Alan Gouger]

Shawn

David is correct.

Yes the image starting out from the Panamorph was smaller but I had to zoom the projector up to fill the screen so it was the same size as the other lens.

In the end when I took the pictures they were all on equal basis.

[sfogg]

"That is a totally false assumption. It shows clear confusion of the principles of how it works."

I understand exactly what the end result of the entire system is doing. I'm not talking about that. I'm talking about the operation of the optics of each anamorphic lens itself.

One concentrates light vertically, the others expand it horizontally.

One lens put in front of a projector *always* makes the resulting picture smaller, the others make it larger.

From there to get to your desired screen size you need to alter throw or zoom.. or in the case of the Prismasonic you also have the option of changing the ratio of itself as well.

"... The only main difference is throw distance to screen."

Which shows the completely different operation of the optics of the anamorphic lenses.

Take a projector and put an image up on your screen.

Now put a Panamorph in front of the screen. The width of the image stays the same but the height is reduced. The vertical angle of the light leaving the lens is *smaller* then the angle of the light entering the lens. The picture is compressed vertically and the total area of the picture is smaller. So any color seperation caused by the lens would be concentrated in a smaller area by the very action of the lens.

Now take the lens off again and put on a ISCO or a Prismasonic. Now the image is the same height as no lens but it is expanded horizontally. The total area of the picture is larger. The horizontal angle of the light leaving the lens is greater then that entering the lens. The picture is expanded horizontally and the total picture area is larger then without a lens. So any color seperation would be made larger by the action of the lens.

What the lens does optically does not change no matter what screen size you are setting up with the lens except in the case of changing the Prismasonics ratio.

If you want a larger image on the Panamorph you either need to increase the throw distance or you zoom out the projector. But the Panamorph is still reducing the vertical angle of light leaving the lens compared to what is entering it.

On the flip side the ISCO or the Prismasonic the angle of light leaving the lens horizontally is greater then the angle of the light entering the lens.

Shawn

[sfogg]

Alan,

What happens to the 'ca' on the Prismasonic when you increase or decrease its ratio from the 1.33 of the other lenses?

Shawn

[pocoloco]

I've had some time with the prismasonic H lenses. CA is dependent on how much the light is stretched. the more you stretch the image, the more CA is visible. Vice versa.

[sfogg]

One other point to consider. Each of these lens is in effect distorting the picture size. One distorts vertically, the other horizontally. This works because the picture is distorted either by the projectors scaling and HTPC or a scaler.

To achieve the 16x9 ratio from a 4x3 starting point the vertical lens model needs to distort the picture less then the horizontal models.

The multiplication (size distortion) ratio of a horizontal lens model is 1.33x1.

The multiplication (size distortion) ratio of a vertical lens model is 1x0.75.

So if you just look at how much the lenses are altering the picture size (and ignore the direction of the picture change) the horizontal models need to introduce 32% more 'distortion' to the picture to achieve a 16x9 ratio image then a vertical compression model.

That makes it not suprising to me that other types of distortion are lower as well.

Shawn

[Morbius]

Originally posted by sfogg

It isn't suprising that the color seperation of the panamorph is smaller since it is working in the opposite direction of the other lenses. If the Panamorph has 'ca' it is reduced by the very action of its compressing the image passing through it. It is concentrating the light passing through it.

The other lenes are making the picture larger, IOW expanding the light passing through it. That expansion will make color separation more obvious.


Shawn,

The color aberration of a lens does NOT depend on whether it is expanding or compressing
the image - please consult any text on optics.

Expansion does make the "CA" more obvious - but as I pointed out - even though the
Panamorph may be compressing the image - if it introduces "CA" - that "CA" will be just
as obvious - because other lenses in the chain are going to magnify the image so that
it fits properly on the screen.

[sfogg]

I never said that compression the image won't create CA. I said that the action of comrpessing the image will make it less obvious.

"Expansion does make the "CA" more obvious "

Now you are agreeing with what I've already posted.

"Panamorph may be compressing the image - if it introduces "CA" - that "CA" will be just
as obvious - because other lenses in the chain are going to magnify the image so that
it fits properly on the screen."

Which occurs BEFORE the action of the Panamorph lens, not after it. So there is no lens that is going to magnify the CA that may be introduced by the Panamorph. The Panamorph is the last lens in the chain.

Shawn

[David Wallis]

One concentrates light vertically, the others expand it horizontally.

One lens put in front of a projector *always* makes the resulting picture smaller, the others make it larger.

So there is no lens that is going to magnify the CA that may be introduced by the Panamorph. The Panamorph is the last lens in the chain.



Boy Shawn you are just trying way too hard to "out think" what in reality is actually going on. You have a beginning (Projector) and an end (Screen) with a middle (Optics) determining the mounting position limitations (for screen focus).

Producing less CA has nothing to do with whether an anamorphic lens compresses or expands, because the beginning and the end of the story are fixed. Less CA is mostly just better optical qualities. All lenses can be improved on no matter what method you chose (compress or expand).

The crux that brings a level playing field in this expand vs compress difference is the same screen size, where the projector is mounted is irrelevant if its within its operational range.

DavidW

[noah katz]

It seems to me that because an expanding anamorphic lens takes diverging rays and increases the angle of divergence that it would increase CA,while a the opposite would be true with a compression lens.

The argument that it doesn't matter because the beginning and end points are the same is not always true depending on the setup restrictions and throw range of the pj.

[sfogg]

"what in reality is actually going on."

Are you trying to claim that this:

One concentrates light vertically, the others expand it horizontally.

One lens put in front of a projector *always* makes the resulting picture smaller, the others make it larger.


Isn't exactly what the respective lens do? The whole reason you need to alter throw or zoom is because of the above. So to claim that isn't 'what in reality is actually going on' is quite a stretch.

"Producing less CA has nothing to do with whether an anamorphic lens compresses or expands"

Wrong.

As I already said the optics in a vertically compressing lens need to make less of a change to the projected image then the optics in a horizontal expansion when converting a 4x3 image into a 16x9. The less a lens alters the image (all else being equal) the less the lens will have secondary distortions like ca. As can be demonstrated by lowering the expansion ratio on a Prismasonic and seeing ca reduce. Even if you then go back and make the picture the same as before with the zoom or throw ratio.

If you doubt that a vertical compression lens alters the picture less then a horizontal lens you need to recheck your math.

Shawn

[Alan Gouger]

Shawn

You made 2 statements, you are able to zoom through a good portion of your projectors zoom range using the Prismasinic (you are lucky) and a vertical compression lens gives better performance than a horizontal stretched lens.

I would think the V series would be your preference.

If you try one and see improved performance let us know how it works out. I have yet to try one.

[sfogg]

Hi Alan,

"I would think the V series would be your preference."

Because of the depth of my room I'm limited in the throw I have available. As such to get the screen size I want I need the horizontal expansion of the lens to get to my desired screen size with the throw I have available.

Shawn

[Vern Dias]

The fact of the matter is that with a properly designed anamorphic lens, there should be NO chromatic abberation whatsover.

When was the last time you saw CA in a movie theater?

The companies that are making these lenses are clearly not of the same caliber as Schneider, Kollmorgan, Bausch and Lomb, Panavision, or any of the companies who manufacture commercial anamorphic adapters for 35mm use in movie theaters.

To me, any CA is unacceptable. I even returned a pair of prescription eye glasses a few years ago, because the lenses were made from a cheap polycarbonate that had unbelievable levels of CA. I told him that if he couldn't come up with a plastic lens that didn't have the issue, I would take a glass lens instead.

Since it seems that no one can build a high quality anamorphic lens, I guess my next projector will be a 1080P and I'll just crop it down to 720 or so on the height to match my 2.40:1 AR screen.
Vern

[Alan Gouger]

The companies that are making these lenses are clearly not of the same caliber as

Vern you are absolutely correct.
I have a small 35mm film collection and I have several scope lens and none have CA.
Theres no excuse for our HT lens concidering the 35mm scope lens has to horizontally stretch the image further than our anamorphic 16x9 lens and they do it with no trouble and they are cheaper even with high end coatings and all.

[EvanB]

So, who'll be the first to come out with a consumer lens with no CA or distortion at a reasonable price?

[David Wallis]

The argument that it doesn't matter because the beginning and end points are the same is not always true depending on the setup restrictions and throw range of the pj.
Throw distance by itself has absolute no bearing on CA and so what the lenses do or don't do to alter the throw distance has no bearing on the outcome of CA. If the screen size is the same, the resolution and projector the same then the additional CA is from bad optics not the method. Shawn is just overworked what happen as the light go's through the lens but all things being even the expand or compress has no bearing on CA (unless its bad optics or a bad design). Look at the Yamaha Dlp for a bad case of CA from pushing optics beyond their capabilities.

As Alan and Vern said the proof is in the pudding by having no CA on 35mm scope lenses which expand the image. Shawn is just reporting specific model findings of bad optics, where the fact is at the moment the Panamorph is just better than its opposition (optically). This expand/compress method thing is just off base as far as CA is concerned. Hell no one would make expansions lenses otherwise.

DavidW

[Brandon B]

Originally posted by Vern Dias
The fact of the matter is that with a properly designed anamorphic lens, there should be NO chromatic abberation whatsoever.

Agree with this.

Originally posted by Vern Dias
The companies that are making these lenses are clearly not of the same caliber as Schneider, Kollmorgan, Bausch and Lomb, Panavision, or any of the companies who manufacture commercial anamorphic adapters for 35mm use in movie theaters.

Have to disagree with this in the case of Isco:

http://www.iscousa.com/history.htm

They are one of those companies. However, it would seem they have not brought any of that technical ability and quality to bear on this particular product, so in that sense, you are correct.

BB

[anssi]

Hello from Finland everyone,

I'm the designer of Prismasonic lenses, and I would like to say my points of view to this thread. I have spent hundreds of hours for testing the different type of lenses for home theatre use. First thing to point out is that home theatre projectors are much more challenging for the anamorphic lens attachments than the movie theatre projectors. This is because of the fact that home theatre projectors have much much shorter throw optics compared to movie theatre ones. The amount of geometrical distortion as well as chromatic aberration has direct relation to the projector optics. Longer the throw, better the results. Also you will naturally need the lens of bigger optics in home theatre for the same reason.

When it comes to discussing the vertical squeeze versus horizontal stretch models, I think they both have their andvantages. Manufacturing both vertical squeeze and horizontal stretch models I can say that the chromatic aberration is much better under control with the vertical squeeze models. This is true with all types of projectors, but especially with projectors of short throw. If it is so then why the horizontal stretch? There are three reasons.
1) If one wants to get bigger image from same distance. This need comes often with long throw projectors.
2) If one wants to get constant height 2.35:1 setup, and full panel resolution both with 16:9 and 2.35:1 movies. This is very easy to set up with the variable horizontal stretch. Zooming the projector or removing the lens is not needed. Of course this same goes for 4:3 to 16:9 conversion.
3) Geometrical distortion is smaller with H-lenses. One reason for that comes from the zoom position which can be set to minimum and still achieve the large picture. The picture must be zoomed much larger with the V lens to have picture of same size.

H-1000 lens was designed to have advantages of horizontal stretch with minimal chromatic aberration. Both prisms of lens are acromatic, which means that one prism is made by two prisms having different polarity, angle and dispersion constant. In theory the chromatic aberration should be 70 % smaller compared to the horizontal stretch device with single prisms.

Best Regards,
Anssi Leppanen
Prismasonic

[sfogg]

Anssi,

Thanks for joinging the discussion and giving your findings on the topic.

Shawn

[Morbius]

Originally posted by David Wallis
Boy Shawn you are just trying way too hard to "out think" what in reality is actually going on. You have a beginning (Projector) and an end (Screen) with a middle (Optics) determining the mounting position limitations (for screen focus).

Producing less CA has nothing to do with whether an anamorphic lens compresses or expands, because the beginning and the end of the story are fixed. Less CA is mostly just better optical qualities. All lenses can be improved on no matter what method you chose (compress or expand).

The crux that brings a level playing field in this expand vs compress difference is the same screen size, where the projector is mounted is irrelevant if its within its operational range.

DavidW

David,

Exactly correct.

When the Panamorph creates its CA, it of course does so after squeezing the image - so
the aberration is squeezed into a smaller space - and would be less noticeable if one were
to look at the image directly out of the Panamorph. However, you don't look at the image
directly out of the Panamorph - you put it on the screen. The other optics in the system
will be zoomed so that the image fills the screen - and those optics will expand the
image so that the CA is more noticeable.

The ISCO expands the image itself, so that when the system is zoomed to fill the screen,
the other optics will expand the image less [ relative to the Panamorph ] because the
ISCO does some expansion itself.

Consult any optics text - CA doesn't depend on expansion or squeeze - but on the factor
by which you are altering the aspect ratio. Both lenses alter the AR by a factor of 1.33.
In the case of the ISCO you multiply by 1.33; the Panamorph divides by 1.33 [ 0.75 is
the multiplicative inverse of 1.33 ]

The numbers only look different because of what you call the numerator or denominator.

Look at it this way. Turn your head 90 degrees. In that case the Panamorph does a
vertical expansion [ in your rotated coordinate system ], and the ISCO does the
vertical compression [ with appropiate zoom applied]. If you applied the expansion /
compression "logic", one would have to come to the opposite conclusion as before.

The CA can't depend on what coordinate system one uses - that why the compression /
expansion "theory" is invalid.

[EvanB]

Anssi,

What about one side of the screen being sharper than the other on your prisms? Is something not right here?

Evan

[Vern Dias]

This is because of the fact that home theatre projectors have much much shorter throw optics compared to movie theatre ones.

Sorry, I can't agree with this.

I happen to have a pair of 35mm projectors and a 16mm projector in my HT with B&L anamorphic lenses ca. 1954 or so. I doubt that the active element in an LCD, DLP, or DILA is much, if any, smaller than the image area of 16mm film.

Running the same size image, the same throw ~23' and have NO ca at all.

When I make the move to a new (probably Sony Qualia) projector, it will have the same throw as my 35mm projectors. (and IF I use an anamorphic lens, is will be required to have no more ca than my B&L lenses have today.

One significant difference: Most 35mm anamorphic adapters have an adjustable element that corrects for astigmatism caused by the uneven expansion of the image. Those that don't have an adjustable element (Super or Ultra Panatar) have a fixed element that is specific to a throw range.

Just my observation.....

Vern

[anssi]

Originally posted by Morbius

Consult any optics text - CA doesn't depend on expansion or squeeze - but on the factor
by which you are altering the aspect ratio.

The CA can't depend on what coordinate system one uses - that why the compression /
expansion "theory" is invalid. [/B]

That is correct if both vertical and horizontal devices are made by similar prisms, and if the manipulated picture is square before the squeeze/stretch.

In case of 16:9 projector horizontal axis is 1.77 times longer than vertical. Vertical squeeze lenses, where prisms are symmetrical to the horizontal axis, compress the shorter vertical leg, and act as a window to the longer horizontal leg. CA is formed to the horizontal lines instead of vertical lines, and can be seen in top and bottom of the picture.

In horizontal stretch lens prisms are symmetrical to the vertical axis, and thus they manipulates the 1.77 times longer horizontal leg of picture, and leaves the vertical axis as it is. CA is formed to vertical lines mostly to the left and right edges .

If the picture was square, it would result similar CA in both V and H lenses. However, now the horizontal axis is 1.77 * vertical axis. This means that horizontal stretch lens 'see' the picture as projector had 1.77 times shorter throw, compared how vertical squeeze lens 'see' it. This is the only reason why vertical squeeze lenses are doing better job compared to the horizontal stretch lens made by similar prisms.

If one would want to do 16:9 to 4:3 conversion, this could be done either by horizontal squeese or vertical stretch devices. In this case the stretch device would result less chromatic aberration.

:rolleyes:



What about one side of the screen being sharper than the other on your prisms? Is something not right here?
[/B]

The tested lens is a pre production beta version without coatings. So far no customer has complained us about this issue, so most propable there is something wrong in that unit. Hopefully Alan can use the lens anyway.

Best Regards,
Anssi Leppanen
Prismasonic

[Dan Hitchman]

Can we see some full screen shots with a 2.35:1 movie and also grid patterns?

Alan,

What are you using as a scaler? A HTPC or outboard unit?

[Alan Gouger]

Dan

Would not do any good. To fit the wide image in my camera I have to get so far back you would not gain any detail from the cross hairs.
I used a program called Displaymate on a HTPC.

I have posted numerous pictures in the past to the forum of movie contant full scope. Here are a few.
http://gallery.avsforum.com/data/509/2Picture_006.jpg
http://gallery.avsforum.com/data/509/2Picture_009.jpg

[xiaoyu]

Hi Alan,

Thanks for your excellent work. This is the result that I am looking for.

The Prismasonic H-series and the ISCO II are belong to same horizontal stretch group, but Prismasonic V-series and Panamorph are in different group. Do you have V-series in hand for comparison?

Xiaoyu,

[xiaoyu]

Originally posted by anssi

The tested lens is a pre production beta version without coatings. So far no customer has complained us about this issue, so most propable there is something wrong in that unit. Hopefully Alan can use the lens anyway.

Best Regards,
Anssi Leppanen
Prismasonic [/B]

H Anssi,

I have 4X3 projector for 5 years and I had tried Panamorph 752 and ISCO II few years ago. The CA doesn't bother me too much, but I couldn't stand for non-uniform focus. I finally decided to keep ISCO II and sold the Panamorph.
I just bought Z2. I can't use my ISCOII, since the throw distance become too short when put the lens on. I am in the market for vertical compression lens. Alen's shoot out didn't include Prismasonic V-series lens, which would be a good candidate in comparing to Panamorph. Can you tell me that is your V-series lens comparable to ISCOII in regard the picture sharpness?

[tetra-pro]

Slightly OT, here (http://home.c2i.net/ahustvedt/lens.html) is an interesting link to a home-made anamorphic lens project.

[anssi]

Originally posted by xiaoyu
H Anssi,

I have 4X3 projector for 5 years and I had tried Panamorph 752 and ISCO II few years ago. The CA doesn't bother me too much, but I couldn't stand for non-uniform focus. I finally decided to keep ISCO II and sold the Panamorph.
I just bought Z2. I can't use my ISCOII, since the throw distance become too short when put the lens on. I am in the market for vertical compression lens. Alen's shoot out didn't include Prismasonic V-series lens, which would be a good candidate in comparing to Panamorph. Can you tell me that is your V-series lens comparable to ISCOII in regard the picture sharpness?


I have not tested isco II lens so I can not compare it with V-series. However, you can find some positive customer reviews from this forum.

It is funny that a common presumption is that H-lenses do not fit almost any projector. However, we have been running them with Z2, Z1, HT1000, H30, H56, AE500 without problems. These all are quite short throw projectors. Even some range of zoom can be used. With shortest of these HT1000 and AE500, however, the CA can become too large, and thus H-1000 or V series can be more appropriate.

I also agree that CA is not the most disturbing thing in home theatre. It can be easily seen in test grids, but not in real movies. In my opinion for example the vertical banding (LCD feature) is much more visible and disturbing than the small amount of chromatic aberration.

Best Regards,
Anssi Leppanen

[Armin2]

Anssi,
how much is an anamorphic lens system influenced by a CA from the pj optic system.
I´ve played around a couple of times with the Runco VX-5000 and like the image because the CA free optical system more then for example newer technology projector without this specific lens system.

Best
Armin

[anssi]

Originally posted by Armin2
Anssi,
how much is an anamorphic lens system influenced by a CA from the pj optic system.
I´ve played around a couple of times with the Runco VX-5000 and like the image because the CA free optical system more then for example newer technology projector without this specific lens system.

Best
Armin


I think you mean the misalignment of projector's RGB panels. In best case if the misalignment is to the opposite direction than CA from anamorphic lens, it can even compensate the picture. And of course if it is to the same direction, it will make the CA larger. Fortunately the modern LCD projectors don't suffer much from this feature, and 1 chip DLP projectors can not have the RGB misalignment. Their down side is the rainbow effect caused by the color wheel.

Best Regards,
Anssi Leppanen
Prismasonic

[Armin2]

Anssi,
i realize a lot of symptoms like CA in single chip DLP. Mostly with wide angle optics.
As you can see, i don´t call it CA, but what is it, if it is not CA?

Best
Armin

[xiaoyu]

Originally posted by anssi
I have not tested isco II lens so I can not compare it with V-series. However, you can find some positive customer reviews from this forum.

Best Regards,
Anssi Leppanen

Hi Anssi,

Actually I am comparing your V-series to Panamorph. From Alen's report we all knew the ISCOII is the best in uniform focus area and you said that your H-series which he tested was not the final product, so why don't you send him two demos of H and V series to compare? Don't you think this will be good for your business? Customer feedback couldn't tell the whole story sometimes, since its based on individule taste. The shootout is the best place to compare. No product is 100 % perfect, its only matter of comparison. Don't you agree?

Xiaoyu,

[Palladin]

This has turned out to be a very interesting discussion of something I understood on a more general level, which has been expanded by the many comments presented here. Bob Wood's gotten a couple of these going in the past few months as well.

Alan, thanks for getting this started and providing the images for illustration.

___________________________________________
Palladin

No matter where you go, there you are

[madpoet]

Alan, if you're still watching this thread... what ratio was your throw with the Panamorph? I'm just curious how close it was to 2.0 or above.

Thanks,
MP

[Alan Gouger]

MP

My Seleco 1 chip is 19 feet from the screem throwing a 6 foot wide 16x9 image.

[madpoet]

Wow, that's a heck of a long throw. Thanks for the info.

[Alan Gouger]

Update:

More lens on the way. Isco has volunteered to send their Isco 3. This lens has the largest aperture and its the one Runco uses.
Its said to not have any pin cushion or CA issues.

Also the newer Solid Panamorph is on its way ( I used the oil filled) as well as
one of the Optimorph lens.

I am hoping within a few weeks to update this thread with the added pictures and comments based on the additional lens after they all arrive.

[gpshumway]

Great news, Alan, I await your update on the edge of my seat...

[Armin2]

OH Alan
you will be amazed. Had the Isco 3 in my hands. Dry them well, it´s a beast. :-)

Armin

[madpoet]

Ahhh, ok... I missed the fact that you were using the older Panamorph. Can't wait for the new results. I was scratching my head over some of the panamorph deficiencies you found that I don't see ;)

[Dan Hitchman]

Yes, but how much will the ISCO 3 be? Will it also work with short throw projectors due to its larger size?

[Mark Petersen]

Originally posted by madpoet
Ahhh, ok... I missed the fact that you were using the older Panamorph. Can't wait for the new results. I was scratching my head over some of the panamorph deficiencies you found that I don't see ;)

Yes it will be interesting to see an objective comparison with the new Panamorph. I have both the old oil filled version (actually 2 of them) as well as the new solid version. The oil filled versions differ signicantly from one another in terms of PQ. The solid version totally rawks. It's hard to see a difference when watching a movie, but with a test pattern or HTPC desktop image the differences are huge. The solid panamorph is very sharp across the entire field.

[anssi]

Originally posted by xiaoyu
Hi Anssi,

Actually I am comparing your V-series to Panamorph. From Alen's report we all knew the ISCOII is the best in uniform focus area and you said that your H-series which he tested was not the final product, so why don't you send him two demos of H and V series to compare? Don't you think this will be good for your business? Customer feedback couldn't tell the whole story sometimes, since its based on individule taste. The shootout is the best place to compare. No product is 100 % perfect, its only matter of comparison. Don't you agree?

Xiaoyu,

Hi Xiaoyu,

I will send our V-500 lens to Alan's shootout this week.

Best Regards,
Anssi Leppanen
Prismasonic

[Gearloose]

Hi Y'all

Maybe consider that the future will be optic specific programs that correct for CA, Barrel, Keystone, etc. distortions of particular lenses. There is a French company, DxO http://www.dxo.com offering such software that offers programs to correct several hi end digicam optics. Eventually, all digital related optics will include such correction, and no reason why this would not include projectors and lens attachments.

[Hotalot]

Alan, any news about ISCO III and Prismasonic v1000?

[Armin2]

@All,
a bit of topc. Had to install a Runco CL-710 with a 0.8 attchment. Choose the Isco. Result is far better then expected.


Best
Armin

[Alan Gouger]

Armin

Glad to hear your positive comments. Isco makes a great product.




Everyone, I am working on getting a few more lens.
Isco, Prismasonic, the new Panamorph will be added to the line up for a part two. This will be a few weeks away.

Thanks for sharing the interest:)

[Steve*Moore]

I received an email from Prismasonic yesterday. Due to the Finnish holiday/vacation period in July, the H1000 will be available in the first part of Augsut.

Steve

[inol]

Have you received the H1000 yet?
Have had time to test it?

[Alan Gouger]

Have you received the H1000 yet?

After Cedia I will be in touch to get the 1000 and I will also have an Isco 3 on its way.

[Mark Petersen]

Originally posted by Alan Gouger
After Cedia I will be in touch to get the 1000 and I will also have an Isco 3 on its way.

Alan, I'll be very interested in seeing how the PSO Panamorph compares to the Isco 3. It should be interesting. I found the PSO to be vastly superior to the P752 Panamorph.

[Craig Peer]

" Everyone, I am working on getting a few more lens.
Isco, Prismasonic, the new Panamorph will be added to the line up for a part two. This will be a few weeks away. " -

Hi Alan. How is " Part Two " going? I'll be interested to hear further lens comparisons, especially if you test a Prismasonic V500.

[PAP]

Bump - part 2?

[Frank J Manrique]

Originally posted by Alan Gouger
I have a small 35mm film collection and I have several scope lens and none have CA.

Theres no excuse for our HT lens concidering the 35mm scope lens has to horizontally stretch the image further than our anamorphic 16x9 lens and they do it with no trouble and they are cheaper even with high end coatings and all.

Well, there it is: it is clear these thingies are really nothing more than a band-aid "cure" for something that needs to be addressed at the very onset of video projectors design.

Actually, am surprised the Isco anamorphic lenses for video use have such fundamentally avoidable optical aberration problems; the sure don't when it comes to film projection applications...just like Vern states...and you have seen with your own eyes. Isco cinema optics are of superior quality. Oh, well.

By the way, Alan...do you know if Isco sells the double-post mount sans the lens? I sure like to get one for my Isco I. ;) Thanks in advance... :)

-THTS

[Brandon B]

I would be really surprised if a 35mm scope lens were cheaper even than the Isco III.

BB

[Alan Gouger]

By the way, Alan...do you know if Isco sells the double-post mount sans the lens? I sure like to get one for my Isco I. Thanks in advance...

Frank I will find out.


Part 2: My Isco 3 will be back to me soon and I look forward to posting more pics for part 2.

[Frank J Manrique]

Originally posted by Brandon B
I would be really surprised if a 35mm scope lens were cheaper even than the Isco III.

Well...be really surprised because I have bought used 35mm anamorphic lenses that ranged between $100 $150. Once I even paid $25 for another scope attachment (used, of course). ;)
The anamorphic Isco lens I really want will cost me far more than that, but much less than any of those costly toys being passed as anamorphic attachments (yep...even my own Isco I lens).

Although not anamorphic, I paid $200 for an Isco spherical ("flat") 70mm lens...the likes that would make you cry; it weights a ton and is almost as big as a LAW missile launcher! :eek: :eek:
And you ought to see the size of the optical glass ends! :eek:
This beauty, which was a twin brother of another 70mm lens that were included in an entire 35/70mm Norelco Todd-AO AA II projection booth that was sold to someone I know, came crated in a beautiful wooden box that protects it when not in use.
This green Isco monster (the body is green anodized) is truly something to behold (at least for those who appreciates fine optics anyway)... :)

-THTS

[Brandon B]

Ah, used.

Yes, you can get them used a lot cheaper, but that's supply and demand. We buy stuff new at my work and that's the pricing I was thinking of.

If high end PJs all start coming out with built in decent switchable anamorphic lens, I imagine Isco IIIs would suddenly be pretty cheap used as well.

BB

[Frank J Manrique]

Originally posted by Brandon B
Ah, used.

Yes, you can get them used a lot cheaper, but that's supply and demand. We buy stuff new at my work and that's the pricing I was thinking of.

If high end PJs all start coming out with built in decent switchable anamorphic lens, I imagine Isco IIIs would suddenly be pretty cheap used as well.

BB

And here I thought we were talking about QUALITY of optics. Silly me! :D

The fact is that even though the film projection lenses were bought used they have perfect optics...while the Isco I video thingy doesn't and it cost me over $1K, brand new, to get it... ;)

-THTS

[Brandon B]

True. According to Alan, though, the new Isco III has no CA and is more in line with the quality of the lenses you have.

But with the rather low quantity market it represents, they probably price it at that point out of (some degree of) necessity.

Sort of seems like they have sort of been feeling their way into the HT market.

Isco I - "HT types have projectors with pretty mediocre lenses in them. We don't need to make the lens super high quality."

Wrong. At $2K+ you do.

Isco II - "OK we'll boost the quality some and we should get more of a response."

Strike two. Same reasoning.

Isco III - "OK, looks like even though their existing lenses are not top quality, they won't accept ANY further degradation. We'll make it good quality. But at the volume these have been moving, we're gonna charge a lot more than we have been."

Or something like that maybe.

BB

[Frank J Manrique]

Originally posted by Brandon B
True. According to Alan, though, the new Isco III has no CA and is more in line with the quality of the lenses you have.

But with the rather low quantity market it represents, they probably price it at that point out of (some degree of) necessity.

Sort of seems like they have sort of been feeling their way into the HT market.

Isco I - "HT types have projectors with pretty mediocre lenses in them. We don't need to make the lens super high quality."

Wrong. At $2K+ you do.

Isco II - "OK we'll boost the quality some and we should get more of a response."

Strike two. Same reasoning.

Isco III - "OK, looks like even though their existing lenses are not top quality, they won't accept ANY further degradation. We'll make it good quality. But at the volume these have been moving, we're gonna charge a lot more than we have been."

Or something like that maybe.

That's some REALLY funny ****, dude!... :D :D :p

-THTS

[inol]

If I remeber correctly there were more test to be added
to this thread.

Was there/Wll there be?

[Oswald Pascual]

Alan

That is excellent work, and a fantastic service to us users!

I also want to thank the AVS forum for getting me a good deal on my Stewart screen I recently ordered.

Ozzie

[Alan Gouger]

inol

I apologize. I have been so busy that Im backed up on projects. I will get to this over the next few weeks. Promise:)


Ozzie

Thank you:)

[djbluemax1]

Would be great to see results from the updated shootout before the Prismasonic Powerbuy ends if at all possible.

[inol]

Alan,

No need to apologize, I was just curious to see what's happening.
I am looking forward to see the next part.

Thanks for the excellent work you have done so far!

All the best,

Ingvar

[djbluemax1]

Alan,

Any ideas on the possibility of the 2nd shootout before the Prismasonic Powerbuy ends? Really curious to know what the CA, focus uniformity and geometric distortion differences are between the V-500 and the H-1000 since Anssi seems to have commented that it's more difficult to minimize CA with a horizontal expansion lens vs. vertical compression.

I'm also interested in the geometric distortion differences between the Panamorph and the Prismasonic V-500.

Really appreciate the time you've taken to do the first shootout for those of us looking at the different anamorphic lens options, and very eager to see the next round.

[Alan Gouger]

I doubt I will get to it by time the sales end because my system is undergoing some upgrades.
I have been using the 1000 and the CA is greatly reduced over the 500. I like the lens allot. There is no geometry distortion with the 500h or 1000h.
I have not tried the v series so I cannot comment.
I will get to this as soon as I can. Thanks!

[tvted]

Originally posted by Alan Gouger
I doubt I will get to it by time the sales end because my system is undergoing some upgrades.
I have been using the 1000 and the CA is greatly reduced over the 500. I like the lens allot. There is no geometry distortion with the 500h or 1000h.
I have not tried the v series so I cannot comment.
I will get to this as soon as I can. Thanks!

Alan,
I left you a question in the Powerbuy thread (http://www.avsforum.com/avs-vb/showthread.php?postid=5217624#post5217624) for the Primasonic. I can read you are busy, but do you think you could provide me with an answer before the offer runs out. :D
It shouldn't require too much typing.;)

thanks,
ted

[Alan Gouger]

Hi Ted

Ive asked Anssi to answer those questions to provide accurate answers because some of those questions relate to the V series which I have no experience or to the procedure of the sale. Please note this is not my sale its Prismasonics hence my disclaimer. In ether case he has replied including answering your question. Thanks!

[raoul]

Alan,

If you were buying a JVC HX2 would you go for the Panamorph SX21 A. I'm assuming that this lens is perfectly suited to the machine and will have no focus problems. My only concern is that it'll do away with my constant height idea.

R-S

[Alan Gouger]

Raoul

Yes it should work and provide great performance. I cannot comment based on personal experience but if the lens has the aperture for this projector then it should yield excellent results.

[raoul]

I'm trying to choose between the Prismasonic and the PSO SX21. Given that the PSO costs more and bitches my plans for a constant height setup I'm not 100% I want to go that way but from your review it's a great lens and makes mounting the lens a snap (literally).

Actually, I'm wondering if one could still do constant height, using an external scaler, using this lens. I want SCOPE 2.35:1. Would using a scaler to make the setup run constant height cause too many artifacts?

R-S

[raoul]

Alan,

What contributed to the geometric distortion on your Panamorph in the shootout? With my lens set to a really long throw, I can mount my projector about 22-24 feet away from the screen (10 ft wide). Would this minimize the keystone/barrel distortion?

If geometry distortion is something I really don't want to deal with should I be considering the Prismasonic instead?

R-S

[Alan Gouger]

Yes zooming your projector to its smallest image gives better performance with all these lens. The slight distortion with the Panamorph is not noticeable when viewing movies and is very slight in my opinion.
My one complaint with all anamorphic attachments except the Isco3 is limited aperture on all of them. I dont understand why they were not made larger from the get go seeing as most projectors have short throw lens. Ive had problems with this from day one. They should all be twice the size they are now and by doing so this would guaranty them to work with all projectors and giver better performance.

[Dan Hitchman]

I would assume that the new, "inexpensive" Sharp HD2+ DLP projector has too short a throw for an H-1000, correct? Or would it work, but with distortions?

Thanx!

[Alan Gouger]

Dan

The new Sharp has a nice long zoom and will work well.

[scottyb]

Any new comment on lenses?

scott

[gobrigavitch]

Alan just curious if you're nearing completion of Part 2 of your anamorphic lense shootout.

I've never really considered a constant height setup, but I'll likely upgrade my PJ in the next year and I"m thinking of using an anamorphic lense. It sounds like the Horizontal lenses are definitely the user friendly way to go.

I understand that the H79's Letterbox zoom will vertically stretch a 2.35:1 movie so that it can be used with a horizontal stretch lense. Does that mean that any PJ with a zoom for letterbox movie will work with an anamorphic lense or is there something special about the H79 zoom.

Thank you

Greg

[GetGray]

Greg: Just a point of clarification, the H79's letterbox mode is suitable for an anamorphic vertical squeeze or a horizontal stretch lens. I'm also considering a anamorphic lens, and while I like the idea of constant height, the size I want may be a "stretch" for my lumens :)

[gobrigavitch]

Currently I have a 58"V x 104"H I'd like to keep the same height and add width with the anamorphic lense if I go that way. I've heard the H79 is putting out 500 in low and 600+ in high so should handle it. I like the idea of the knobs on the panamorph h1000 to dial it in or out.

[Dan Hitchman]

Does the Optoma H31 have the same "letterbox mode" or is this a unique scaling feature of their higher end models?

Is the throw ratio of that projector suitable for an anamorphic lens like the Prismasonic H-1000 anyway, or is it just too short?

[Alan Gouger]

Regarding projectors with the needed letterbox mode my experience is most do not have this and the ones that do are limited in that its only available on certain inputs and for NTSC and may not work for HD. Sim2 projectors are the only projectors I have found that offer custom aspect ratio on all inputs for all sources. I think every manufacture should offer this. Even those charging top dollar strip this features from the DVI input . You will have to do your homework on which projector will offer this or buy an outboard scaler such as the Lumagen/Iscan/Faroudja/Crystallio ect to do the work for you.

I have yet to do the pictures for part two but heres some quick notes that should help.

I now have the Isco 3 and the Prismasonic H1000.

The H1000 offers improvement in Chromatic Aberration over the 500 series with better optical coating, less reflection. I like this lens allot. I like the fact you can leave it in place and regardless what ratio you choose you are always using the projectors full panel resolution. For those who want the best between the two I would go with the H1000 but the H500 is still a great lens as well if you dont mind the minor additional CA. Otherwise they appear the same in performance.

I also now have the Isco 3. Because our dollar is so weak to the euro this lens is not cheap but for those wanting to do a constant height setup this is hands down the best lens of them all. Razor sharp center to corner with very little if any and I want to say no chromatic aberration at all. Very very slight pic cushion. This is the only lens that when placed in front of the projector you see no loss in contrast or sharpness as if the additional glass is not there. All the other lens do soften the image slightly or have a slight effect on contrast.
The Isco 3 also has a very large aperture so it will work with any short throw projector in any zoom position. No worries. This lens is reference. Its not cheap but anyone serious about doing a constant height setup it will be the last lens you will ever need to buy so its a one time life long investment.

Thanks

[GetGray]

Just an FYI, the Optoma H79 does do the vertical stretch that takes a 2.35 DVD and fills the entire panel vertically. It strips off a couple lines at the top, but that's not too bad IMO since it removes the external scaler requirement. It does scale on all it's inputs, including 720p from my Denon 3910 DVD.

[ckmartinez]

Alan - If I was to use the ISCO 3 for a constant height set up involving a JVC hd2k, would I need to move the lens out of the way for 1.85 and 1.78? If so, does ISCO make a motorized housing for the ISCO 3?

Also does the ISCO 3 change either the throw distance for the projector or the projector's lens offset position?

Thanks!

[tvted]

Originally posted by Alan Gouger
Regarding projectors with the needed letterbox mode my experience is most do not have this and the ones that do are limited in that its only available on certain inputs and for NTSC and may not work for HD. Sim2 projectors are the only projectors I have found that offer custom aspect ratio on all inputs for all sources. I think every manufacture should offer this. Even those charging top dollar strip this features from the DVI input . You will have to do your homework on which projector will offer this or buy an outboard scaler such as the Lumagen/Iscan/Faroudja/Crystallio ect to do the work for you.

I sure wish my PJ had ratio control on the HDMI input. T'would certainly save the wife some trepidation with the HTPC and ZOOMPLAYER.


I now have the Isco 3 and the Prismasonic H1000.

The H1000 offers improvement in Chromatic Aberration over the 500 series with better optical coating, less reflection. I like this lens allot. I like the fact you can leave it in place and regardless what ratio you choose you are always using the projectors full panel resolution.
;)

and I like mine a lot too, of which, thanks to your starting this thread, I became aware of.

ted

[WillyGib]

I finally received a usable Prismasonic H-1000 lens. I have a Infocus 4805 and it seems to work great. I use the PJ letterbox mode to do the vertical stretch. I have a Corada 128" 1.4 gain screen. I know I'm pushing the 4805 to its limits but it looks great. My first row of seating is at 13' and I see very little SDE, second row is 19' NO SDE. I still need to tweak the lens since I do have a little bow on the top side. Left, right, & bottom look OK. I need to figure out how to straighten out the top. If I can't get the bow out I'll expand the image and let the screens black border hide the bow.

Very happy with the lens, but this is the second lens I've received due to breakage. This lens has a cracked bezel on the front lens but Prismasonic is sending a new front lens & bezel for me to replace.

[g2uhlj]

I am using the ISCO III with a Runco VX5000D. It is sold with the projector by Runco as part of their Cinewide package. I can state that the picture is quite stunning.

I do see a a very slight pincushion effect, and at the corners of the 2.35 frame I can see a slight "shadow". I wonder if there is some way to reduce this or eliminate this "shadow". It appears only on the right side of the 2.35 frame.

[dust]

I find that when there is a shadow on the side of the 2.35 frame, I need to move my ISCO II lens sideways in the direction of the shadow. On my setup, that shadow comes from the projected image hitting the side of the lens.

[g2uhlj]

How does one move the lens sideways? My projector is suspended from the ceiling, and there is a heavy metal plate on the top of the PJ. There are two arms in groove-tracks that hold the lens. I don't think it can move side to side, but it can move forward and back.

[Alan Gouger]

g2uhlj

If you cant move the Isco lens does your projector have motorized lens shift for left & right?

[g2uhlj]

Yes. I should have thought of that. Shame on me.

I was pretty thrilled to see that Runco is selling the ISCO-III as the anamorphic lens in their Cinewide package. I think almost all of the extra cost ($6000) must be wrapped up in the lens. Does anyone know what an ISCO-III retails for? I think the ISCO-II is around $2,000 or $2,500. I was curious.

[Alan Gouger]

The Isco 3 bought separate cost around 4k.

Once you use the lens shift on the projector to center the image on the Isco lens you will most likely have to physically twist the projector a tad to compensate to re align the image to the screen.

[g2uhlj]

Alan, do you have any suggestions for reducing the pincushion effect on the Isco-III lens? Would keystone correction help?

[Alan Gouger]

Originally posted by g2uhlj
Alan, do you have any suggestions for reducing the pincushion effect on the Isco-III lens? Would keystone correction help?

The use of electronic keystone in the projector will not help but the tilt of the anamorphic lens will change this. By tilting the lens you can even out the pincushion top/bottom or add more to the top verses the bottom or vis versa.
Keep in mind any tilting of this lens will require you to re shift the projectors primary lens until you get everything centered on your screen again. If you do not feel comfortable doing this I would leave everything alone until the next visit from your installer/dealer.

The lens if tilted and centered should give minimum pincushion that should not be visable if you have slight over lap onto your screens black boarder.

[tvted]

Originally posted by g2uhlj
Alan, do you have any suggestions for reducing the pincushion effect on the Isco-III lens? Would keystone correction help?

I believe pincushion is inherent in the nature of a convex lens. It is reduced by utilizing the more central portion of the glass where the slope of the convex arc is less and the smaller image occupies a smaller portion of that arc. Another solution would be more glass - say a concave element to invert the cushion shape.

Then again I could be mistaken. :confused:

ted

[gobrigavitch]

I'm trying to decide between the H500 and H1000 prismasonic lenses. Alan, on those pictures you took there was some CA visible on the h500, but how far from the screen was that picture taken. Is it noticable on movie viewing from lets say 1.2x the cinemascope width. Also on pass-through mode is there any CA? I think CA would be most distrubing on HD sports on the tickers and scores, with their white lettering. It will be a bit of financial stretch to get the H1000, but if the H500 will have noticable flaws, I'll spend the difference.

[Alan Gouger]

[QUOTE=gobrigavitch]I'm trying to decide between the H500 and H1000 prismasonic lenses. Alan, on those pictures you took there was some CA visible on the h500, but how far from the screen was that picture taken. Is it noticable on movie viewing from lets say 1.2x the cinemascope width. Also on pass-through mode is there any CA? I think CA would be most distrubing on HD sports on the tickers and scores, with their white lettering. It will be a bit of financial stretch to get the H1000, but if the H500 will have noticable flaws, I'll spend the difference.[/QUOTE]


I dont think you will notice CA on pass through on ether the 500 or 1000.
It does show up more in 235:1 mode on the 500 compared to the 1000.
Most important I find the optical coatings on the 1000 to be better then the 500. The 1000 has greatly reduced reflections from the prisms that equates to better contrast. I do think the 500 is not a bad lens but I feel you will want to upgrade. Buying the 1000 upfront and you will have no need to upgrade later.

[Dennis Erskine]

Pincushion - The shorter the throw distance (with respect to picture size) the greater the pincushion. We address that problem with a curved stewart screen. To my knowledge, the screen research folk haven't figured out how to do a curved screen yet.

Scalers - Toward the end of this year, Runco will be selling their DHD scaler as a standalone processor. Each scan rate for each input can be individually calibrated.

g2uhlj - The shadow is from improper alignment of the ISCO-III and the primary lens (as Alan mentioned). The ISCO mount allows it to be moved up/down,in/out, and rotated. The internal lens shift in the Runco handles side to side alignment.

[kuzzy]

Dennis,

In your experience with the ISCO III, would a curved screen be necessary with a FP throw ratio over 2.0 (I am planning on mounting my FP about 16-17 feet from a 114 inch 2.35:1 screen (roughly 86 inch wide for 16x9 to base the throw ratio)? If so do you vary screen curvature recommended by based on the given throw ratio?

Thanks,

Brian

[Dennis Erskine]

You're on the border line. I'd suggest you set your projector up at that throw distance, project the image onto a wall and see if the pincushion bothers you.

[Kevin Korom]

Alan (or anyone else with experience), since you've had both, how would you rate the ISCO II vs. the H1000? I have the ISCO II now, and while I'm quite happy with it, I'd love to have a passthrough mode and maybe a little less focus variation from side to side. Any comments would be most appreciated. Also, is the aperture any smaller? The ISCO just barely meets my needs with my HS20 zoomed out all the way; if the H1000 was less I'd be SOL. That recessed lens is a pain.

BTW, I just discovered this new 2.35 forum (great idea)- are we lowly under $3500 digital PJ owners allowed in here?:D

[Alan Gouger]

Kevin

The H1000 is better then the Isco2 in a few ways.
Larger aperture. No pin cushion. Pass through mode. Better edge focus. I think you will be very pleased with the performance of the H1000.

[techman707]

[QUOTE=Vern Dias]The fact of the matter is that with a properly designed anamorphic lens, there should be NO chromatic abberation whatsover.

When was the last time you saw CA in a movie theater?

The companies that are making these lenses are clearly not of the same caliber as Schneider, Kollmorgan, Bausch and Lomb, Panavision, or any of the companies who manufacture commercial anamorphic adapters for 35mm use in movie theaters.

To me, any CA is unacceptable. I even returned a pair of prescription eye glasses a few years ago, because the lenses were made from a cheap polycarbonate that had unbelievable levels of CA. I told him that if he couldn't come up with a plastic lens that didn't have the issue, I would take a glass lens instead.

Since it seems that no one can build a high quality anamorphic lens, I guess my next projector will be a 1080P and I'll just crop it down to 720 or so on the height to match my 2.40:1 AR screen.
Vern[/QUOTE]

Vern,

I can assure you that ISCO (along with Schneider) are MORE than capable of making an anamorphic lens to convert 4:3 AR to 16:9 AR without any problem. For some reason, they have chosen to make poor quality lens and charge MORE for it than a regular theatrical 2x anamorphic lens. You're practically guaranteed to have distortion since ISCO has chosen NOT to provide any astigmatism adjustment on their lens. Before I got an ISCO II lens, I used an old Panavision adjustable prism lens yourself that I had collecting dust and it worked every bit as good as the ISCO lens. But don't fool yourself, if you go up to the screen in a theatre with a large screen (not the boxes they build today), you an see some CA.


Bruce

[Vern Dias]

Bruce,

I believe that you misinterpreted my post or took it out of context. It was a comment on the sad state of affairs when everyone thought that the oil filled prism lens was going to be the cats meow.

The Ultra or Super Panatar lens that you are currently using had a front element that was ground for astigmatism correction, however if yours even still has it and you look closely you will see a very small 80-100 or 60-80 or 40-60 etched in the front element. These are the throw ranges in feet that the elements were ground to correct for.

Since the posting you cited, I have had the good luck to find a surplus Isco Cinema DLP anamorphic lens with a 1.5 X horizontal expansion factor to use on my Runco. It does have the astigmatism adjustment and can be adjusted to remove any and all astimatism error. The only down side is that it only weighs 20 lbs and is 10" in diameter!!!

As for you comment on CA, having been a professional projectionist and having upgraded, installed and tuned the equipment in many theaters including several theaters with screens exceeding 50' wide, I can assure you that a theater with no CA is perfectly possible, even when standing 5 to 10 feet away.

Vern

[techman707]

[QUOTE=Vern Dias]Bruce,

I believe that you misinterpreted my post or took it out of context. It was a comment on the sad state of affairs when everyone thought that the oil filled prism lens was going to be the cats meow.

The Ultra or Super Panatar lens that you are currently using had a front element that was ground for astigmatism correction, however if yours even still has it and you look closely you will see a very small 80-100 or 60-80 or 40-60 etched in the front element. These are the throw ranges in feet that the elements were ground to correct for.

Since the posting you cited, I have had the good luck to find a surplus Isco Cinema DLP anamorphic lens with a 1.5 X horizontal expansion factor to use on my Runco. It does have the astigmatism adjustment and can be adjusted to remove any and all astimatism error. The only down side is that it only weighs 20 lbs and is 10" in diameter!!!

As for you comment on CA, having been a professional projectionist and having upgraded, installed and tuned the equipment in many theaters including several theaters with screens exceeding 50' wide, I can assure you that a theater with no CA is perfectly possible, even when standing 5 to 10 feet away.

Vern[/QUOTE]

Vern,

You're correct, they ground it for a particular range. It's marked in "cm" and not footage though, however, the problem is from the "one size fits all" mentality to save money. You would think that for what ISCO charge's for these lenses, they would make it adjustable, which really isn't possible on the cheaper prism designs.

You're also correct that it's "possible" for a theatre to have no CA, however, having designed and installed movie theatres for 40 years before I retired, with the exception of lenses from Schneider and maybe ISCO, that isn't the case. Unfortunately, the American made lenses from Kollmorgan and Bausch and Lomb are window glass when compared to lenses made today by Schneider.

Bruce

[Thatchmo]

Alan,

I have the Yamaha DPX-1200 and want to set up a 2:35 screen. My projector's lens is about 15 feet away from my screen wall and I can zoom it up to get a 127" wide letterboxed image at about 54 inches high and at a more modest zoom I can easily get a 96x54 image. I would like to set up a permanent height system going from 96x54 to 127x54. From what you have posted, it sounds like my only option would be the ISCO III. I would love to save some money and have the pass-through mode of the H1000, but it seems that I would be too far zoomed in to use the small aperature of the H1000?

I am I correct in my assumption, or is there hope for the H1000 in my set up?

Thanks for any help,

Kirk

[techman707]

[QUOTE=Thatchmo]Alan,

I have the Yamaha DPX-1200 and want to set up a 2:35 screen. My projector's lens is about 15 feet away from my screen wall and I can zoom it up to get a 127" wide letterboxed image at about 54 inches high and at a more modest zoom I can easily get a 96x54 image. I would like to set up a permanent height system going from 96x54 to 127x54. From what you have posted, it sounds like my only option would be the ISCO III. I would love to save some money and have the pass-through mode of the H1000, but it seems that I would be too far zoomed in to use the small aperature of the H1000?

I am I correct in my assumption, or is there hope for the H1000 in my set up?

Thanks for any help,

Kirk[/QUOTE]

Why would you need an ISCO III anamorphic attachment since the panel size of the DPX-1200 is .9" and the ISCO II is good up to 1.3" panels?

[Thatchmo]

Techman,

I really didn't consider the ISCO II due to this quote by Alan:

[QUOTE=Alan Gouger]

The H1000 is better then the Isco2 in a few ways.
Larger aperture. No pin cushion. Pass through mode. Better edge focus. I think you will be very pleased with the performance of the H1000.[/QUOTE]

If there are reasons why I should consider the ISCO II, I'm open to them....

Kirk

[techman707]

I use an ISCO II and have perfect focus edge to edge. The interesting thing is that I don't see any real chromatic aberration or pincushion distortion. However, that might be different if I used more lens zoom. Also, if the anamorphic adapter isn't close enough to the projector lens, it could cause vignetting also.

[bukiwhitey]

"I would love to save some money and have the pass-through mode of the H1000, but it seems that I would be too far zoomed in to use the small aperture of the H1000?"



Kirk,

According to Alan the H1000 has a Larger aperture than the Isco II, don't know about the III. I would think the H1000 would be suitable for your situation. Maybe Prismasonic can answer this question.

"The H1000 is better then the Isco2 in a few ways. Larger aperture. No pin cushion. Pass through mode. Better edge focus. I think you will be very pleased with the performance of the H1000. "

[Alan Gouger]

Kirk

The Isco 2 is a great lens and sharp focus and great contrast. Very little Chromatic aberration
if you have a long throw lens and use the projector zoomed to a small image.

I have never seen the Yamaha in person ( would love to) so I am not familiar with its lens throw and off set ect. I think you will be fine with the H1000. If you try the H1000 Ansi does offer a money back option so you cant go wrong. A motorized version will be out in a few months also that will adjust the image from 16x9 to 235:1 via remote. I wonder if there will be pre sets or if we stop it in mid travel on our own. I have no information on this other then what i have read on this forum so I am with everyone else waiting to hear further info. Those of us who already own a Prismasonic lens sounds like there will be a retro fit kit for us. Im looking forward to this one.

[techman707]

[QUOTE=Alan Gouger]Kirk

The Isco 2 is a great lens and sharp focus and great contrast. Very little Chromatic aberration
if you have a long throw lens and use the projector zoomed to a small image.
[/QUOTE]

From the testing I've done, it appears that any chromatic aberration you saw probably came from the G15's zoom lens. It appears that the wider the angle the more chromatic aberration is produced by the projector's lens.

[bills2k]

Alan:

You have stated that I can leave my anamorphic lens attached to the PJ at all times. I know that I will be watching mostly movies (95%) and therefore I do not need to move it. What about the other 5% (sports, HD shows and 1.85 movies)? I have ordered the masking system from Don to take care of the pillarboxing but my question has more to do with the PQ. Will I be losing resolution? Will I be using all of the pixels when watching the other 5%?

By the way, thank you for all of your help in making my dreams a reality.

Thanks.

[techman707]

[QUOTE=bills2k]Alan:

You have stated that I can leave my anamorphic lens attached to the PJ at all times. I know that I will be watching mostly movies (95%) and therefore I do not need to move it. What about the other 5% (sports, HD shows and 1.85 movies)? I have ordered the masking system from Don to take care of the pillarboxing but my question has more to do with the PQ. Will I be losing resolution? Will I be using all of the pixels when watching the other 5%?

By the way, thank you for all of your help in making my dreams a reality.

Thanks.[/QUOTE]

This section is supposed to deal with "constant height" screens, but you haven't said what you are using. If you were using a "variable height" screen, the anamorphic lens could remain in place for anamorphic movies (i.e. 2.35, 1.85, etc. ) and the height would change for each format. However, for all non-anamorphic formats, irrespective of aspect ratio, they would have to be scaled with some loss of resolution and/or zoomed if the anamorphic attachment remains in place.

For a constant height setup, only 2.35 anamorphic material can be used without scaling and/or zooming to maintain the constant height, for everthing else, some type of scaling is necessary. This is true even is any type of re-size is used to utilize the maximum pixel surface.

[jmc_007]

Has anyone seen the new H1200, and if so, where does it fit in relation to the other anamorphic lenses available?

Thanks,
Josh

[dusk]

No kidding. I know people are now receiving their new H series lenses. I want to see some more reviews. BTW, the H1200 is virtually identical picture wise compared to the H1000. I think the changes are mechanical only. Anssi or a 1200 owner can maybe elaborate on this.

[wnielsenbb]

Yes, I am really considering the H1200 with the powerbuy on now. I have the prismatic lens now, but the vertical compression makes the image too small for me. A review would be real nice.
Warren.

[wildfire99]

I have a 1200M, however no working projector. Optics look good with my naked eye (staring through the prisms), totally clear. I think the metal stops are a little chintzy but they seem to do the job. I would have preferred something padded and more subtle. The casing is good, being all metal and very classy, with a built-in vertical adjustment. Aperture looks a tad small, especially when both prisms are angled at their max, but it seems to be enough for even my HT1000's largish lens.

Of course, going from pass-through to full-tilt is very easy and a no-brainer with clear labels. Some allen wrenches for adjustment to the stops are included for anyone who wants to tweak the angles.

[Gary Lightfoot]

The aperture is just about big enough with the H7X projectors when the prisms are at the scope position, and this is partially due to the recessed lens in the Optoma. The effect is barely visible, with a little light drop-off at the side edges of the screen, but you'd never notice it during movie watching. It's not a big drop-off like CRTs have btw, maybe 10 to 20% which includes the PJs own light drop-off at the edges (around 7 to 10%)..

Gary

[wnielsenbb]

Thanks Gary. I could live with that. I have a BenQ 7700 so that should be even better. I will be getting one. The remote one will be so nice with a programmable remote. Then I could have it switch modes on the iScan HD+ and the lens together to switch modes. Get the remote masking system and I would be set.
Warren.

[g00f]

I havent had the time to actually test my H1200M with any test patterns yet, but I was successful in getting the full beam thru the aperature; I had issues before with other Anamorphic lenses as the opening was to small for my pj's beam, this was also a factor using a vertical squeeze versus a horizontal stretch so my beam dimensions have decreased.

BUT so far I think its an excellent product, the focus is dead on, and settting it up wasnt that hard to get a great picture, I do have some light spill from my D-ila (g10 clone) but I am planning to try the D-ila Blend method to eliminate it. I have noticed an increase in light output which is one main reason I went with this.

Hopefully this weekend I can grab the PC and throw some test patterns up and check its uniformity and CA. And I have some HDTV movies on the PC from the HDTV Binaries newsgroups and will see how they look and post my thoughts then.

[Steve Scherrer]

OK--this may be a bit off-topic, but I recently acquired a Panamorph P752 (love it!), and notice there are some smudges on the lens itself (probably caused by my own greasy fingers. I'm sure the lens has some kind of coating, so what is the best way to clean these without ruining the lens? I checked the manual and the panamorph website, but did not find the answer. Anyone?

[Jack Gilvey]

This is the info I have from Shawn @ Panamorph:

Windex is what we use. The coatings on those optics is pretty tough. If you need to you can use alcohol as well.


Not sure about the cloth.

[Alan Gouger]

Its been a while and about time for an update. Just received the Prismasonic Motorized H-1200R lens. I have to say the remote is the neatest thing. No longer any need to get up to make the adjustments between aspect ratios. Operation is very fast and quiet. The IR remote works great and has a very wide receiving cone. In fact I found I could point the remote at the screen and the IR signal would reflect back to the lens. Here is a picture of the lens with the remote and one of the lens in place in front of my projector.

http://gallery.avsforum.com/data/509/medium/Picture_008.jpg
http://gallery.avsforum.com/data/509/medium/11.jpg

Here is a description of the technical specs taken from the Prismasonic sight:
The prisms of H-1200 series have been finished by the optical glass
using the highest possible surface accuracy parameters during the manufacturing
process.
This means a crystal clear, perfect focused image with no optical
artifacts.
In addition to this the prisms are achromatic, which means that both
prisms are made by two glass materials having different optical properties.
This specific technology significantly reduces the chromatic aberration from
the image. Moreover, all the optical surfaces have the anti-reflection
coatings to maximize the light output of your projector.

The operation of H-1200R lens is very simple. The other button of
remote stretches the image to 2.35:1 and the other squeezes it back to pass
through mode. Also all the other aspects between those are possible to make.
There are adjustable stops for the prisms so that every one can fine adjust
stretch/pass to match one's own screen/setup perfectly, and after tuning the
switching the modes will be very quick to be operated.

The power for the lens unit is fed by the 12 volts AC/DC adaptor. The
motors are very silent, and it takes about 3 seconds to go from end to end.
This speed enables you also to stop the prisms quite accurate for example to
2.00:1 position.

Remote controller uses 12 volts battery. It has two powerful IR leds,
and can be controlled from the distance of about 12-15 meters from remote, via
screen, to lens unit. If one has an universal remote controller, it is possible
to IR learn it.

There is also a Manual version of the R 1200 but after living with the motorized model for a few weeks I could never go back to a manual lens. Having the choice of aspect ratios at the click of the remote certainly spoils you :)

This lens is very sharp in both the 16x9 pass through mode and the 235:1 mode.
All anamorphic lens tend to smooth out the image and give it a film look or an analog look eliminating that harsh digital edge. I do not call this softening.
I have found that when first setting up this lens you want to set the lens to 235:1 mode then adjust the focus of your projector. This way when you return to 16x9 pass through you will still be in focus. If doing this in reverse for some reason you will be out of focus when stretching the image to 235:1.

Here is a picture of some text at 800x600 with the lens in 235:1 mode. All pictures were taken with a Canon G5 digital camera and the projector was a Sim 300, not very bright but all I had at the time of the review.
Displaying text is a good test for anamorphic lens. This lens passes with flying colors.
http://gallery.avsforum.com/data/509/41.jpg
Another close up. Notice the lack of CA.
http://gallery.avsforum.com/data/509/51.jpg

Here is a good test pattern I use for testing chroma aberration.
Here is a close up of the left side in 235:1 mode.
http://gallery.avsforum.com/data/509/61.jpg
Close up in 234:1 mode right side. As you can see this lens does very well.
http://gallery.avsforum.com/data/509/71.jpg

Please note that almost all projectors have their own chroma aberration unless its a very expensive projector where the lens is sold separate and cost a few thousand on its own. This can be detected better with a 1 chip design because you do not have to worry about mistaken miss convergence of the RGB panels for CA. Adding an anamorphic will only magnify any primary CA. Remember its not always the Anamorphic thats at fault.
I did not take any chroma aberration pictures in the pass through 16x9 mode because that mode looks as if no lens or glass is in front of your projector. I wanted to show worse case scenario which is 235:1 mode. I do not see any reason anyone would not be happy with the performance of this lens. If you buy the remote version you will really be spoiled :)
Nice to watch this product line mature, good job Prismasonic.

[Tukkis]

Alan nice review. My next lens will definately be a motorized one. I think having a motorized lens go in place and motorized curtains open after the trailers for 2.35 movies would really add to the wow factor.