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post #1 of 5 Old 04-27-2020, 09:31 AM - Thread Starter
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Newbie lens Q

I have a JVC RS520 projector and bought an anamorphic lens (Panamorph ELPFALKED) for 2.35 AR movies (I also have a Panamorph P752 lens that someone gave me)
Q - it seems that I have to zoom anyway
Details:
No lens:
When I have the anamorphic JVC setting set to OFF - it shows 16x9 images filling the height of the screen with black bars on the sides of the 2.35 screen (as you'd expect)
When I show as 2.35 AR movie (leaving JVC anamorph OFF) the width is the same (i.e. same black bars on the side) with the addition of black bars above and below the image - again as you'd expect
with Lens:
When I set the JVC to anamorphic setting to "A". It squeezes the image so that the 2.35 image now fills the height (same as a 16x9 would with no anamorphic squeezing except of course everyone looks skinny :-) and noticeably brighter - got me excited ) (i.e. the full projector sensor is being used and projected) and of course same black bars on the sides - again all as expected
HOWEVER
When I put either lens in front of my projector (with the smaller end of the lens closest to the projector) I would expect that it would stretch the image back out to fill the sides (while keeping the height). However, it compresses the image from top and bottom so that the people aren't skinny and look normal, however it's back to where it started with the same black bars on all 4 sides.
So then I need to zoom to get it to fill the screen.

What am I doing wrong, as I thought the point of the lens is to NOT zoom.

thx
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post #2 of 5 Old 04-27-2020, 10:19 AM
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Quote:
Originally Posted by cgott42 View Post
HOWEVER
When I put either lens in front of my projector (with the smaller end of the lens closest to the projector) I would expect that it would stretch the image back out to fill the sides (while keeping the height). However, it compresses the image from top and bottom so that the people aren't skinny and look normal, however it's back to where it started with the same black bars on all 4 sides.
So then I need to zoom to get it to fill the screen.

What am I doing wrong, as I thought the point of the lens is to NOT zoom.
There are two types of anamorphic lenses: horizontal expansion or vertical compression. They both convert a 16:9 image into 2.35:1 using the projector's entire pixel panel, but accomplish it in different ways. The ones you have are vertical compression.

The Panamorph UH480 lens is horizontal expansion, but Panamorph currently only sells vertical compression lenses with the Paladin line.

You will need to use the projector's zoom with a vertical compression lens. However, since you've redirected all of the projector's light into the 2.35:1 image, this should not have any negative affect on the picture quality. It will still be brighter and use more pixels than the same size image without the lens.

Josh Z
Television and Home Theater Writer/Editor, Primetimer.com

My opinions are my own and do not necessarily reflect those of my employers, whomever they may be.
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post #3 of 5 Old 04-27-2020, 11:16 AM - Thread Starter
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Quote:
Originally Posted by Josh Z View Post
There are two types of anamorphic lenses: horizontal expansion or vertical compression. They both convert a 16:9 image into 2.35:1 using the projector's entire pixel panel, but accomplish it in different ways. The ones you have are vertical compression.

The Panamorph UH480 lens is horizontal expansion, but Panamorph currently only sells vertical compression lenses with the Paladin line.

You will need to use the projector's zoom with a vertical compression lens. However, since you've redirected all of the projector's light into the 2.35:1 image, this should not have any negative affect on the picture quality. It will still be brighter and use more pixels than the same size image without the lens.
thanks - though would a horizontal expansion lens be even brighter (as no zooming is involved)?
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post #4 of 5 Old 04-27-2020, 11:35 AM
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Originally Posted by cgott42 View Post
thanks - though would a horizontal expansion lens be even brighter (as no zooming is involved)?
No, it's the same amount of light. The lens' horizontal stretch disperses the light to the same degree that zooming up would. The two different types of lens were designed to cater to users whose projectors have different zoom or lens shift ranges. If you had a projector with limited zoom or lens shift, a horizontal expansion lens could help to fill a larger screen. Conversely, if your projector was mounted at a long throw distance and you couldn't shrink the image small enough to fit on the screen, vertical compression would be needed.

Since JVC has pretty broad range for both features, you can usually get away with either type of lens.

All that said, you should be aware that the older Panamorph lenses may not be able to pass 4k detail from newer projectors. I tried a UH480 lens with a JVC NX7 projector, and the picture was noticeably softer and less detailed than not using the lens. Only the new Paladin lenses can pass true 4k.

I did not test with an eShift projector like your RS520, so I don't know how well that works.

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post #5 of 5 Old 04-27-2020, 11:47 AM - Thread Starter
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Quote:
Originally Posted by Josh Z View Post
No, it's the same amount of light. The lens' horizontal stretch disperses the light to the same degree that zooming up would. The two different types of lens were designed to cater to users whose projectors have different zoom or lens shift ranges. If you had a projector with limited zoom or lens shift, a horizontal expansion lens could help to fill a larger screen. Conversely, if your projector was mounted at a long throw distance and you couldn't shrink the image small enough to fit on the screen, vertical compression would be needed.

Since JVC has pretty broad range for both features, you can usually get away with either type of lens.

All that said, you should be aware that the older Panamorph lenses may not be able to pass 4k detail from newer projectors. I tried a UH480 lens with a JVC NX7 projector, and the picture was noticeably softer and less detailed than not using the lens. Only the new Paladin lenses can pass true 4k.

I did not test with an eShift projector like your RS520, so I don't know how well that works.
Thanks for the info. I've head about that, thus far I've tested it on Star Wars Rise of Skywalker UHD and didn't notice anything (from 10' viewing distance). I'll keep an eye out.
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