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Forgive the length of the following marathon sentence.


I understand the benefits of utilizing an anamorphic lens and scaler for 2.35 projection, but is there any reason why if one has the right balance of long throw zoom lens, throw distance, and screen size and design, that one could not be at a focal length on the zoom (a wide FL) that fills the width of the screen for 2.35, losing the black bars in the wide top and bottom black screen borders, then for 1.78 material zoom in to a focal length (probably near the long end) that brings the top and bottom of the 16:9 panel in to that of 2.35 screen? Yes, there would be unused screen image area on the sides for 1.78.


Would this not also provide the upgrade potential to add either type of anamorphic lens (vertical squeeze or horizontal spread)? With either lens, a scaling function would be necessary to do the vertical stretch.


Would this plan not provide the ability to project both spherical 2.35 and 1.78 on the 2.35 screen, and provide anamorphic lens upgradability? We would just have to add the anamorphic and a scaler, right?


Thanks for checking my logic here.
 

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Yes, but most projectors don't have the zoom range. If you were able to find one with sufficient range, it would have to be mounted at a very exact distance from the screen so that the two extremes of zoom match the height and width of the screen.


Oh, it also better be a 1920 x 1080 projector with excellent fill factor, otherwise you're not going to enjoy looking at the screen door when the lens is zoomed in for scope.


One other thing: not a lot of projectors will zoom and keep the center of the image in the same position on the screen.


Vern
 

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Discussion Starter · #3 ·
Hi Vern,


I've found the PJ w/lens option that will work...and with a little of play on each end to meet the two sizes. Regarding the panel size and your admonishment about the zoom back to scope screen, that is at nominal size/distance/viewing angle (30 degrees). The zoomed in 1.78 would be under nominal just a bit. My point is, I think I'm safe there.

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One other thing: not a lot of projectors will zoom and keep the center of the image in the same position on the screen.
This is a bit of a concern to resolve. Given the projector will be on a Draper lift with adjustable heights, I think I am covered there. Does it sound like it to you?
 

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It's going to depend on the progector. Make sure you test before you buy.


Also, don't forget that it is not unusual to have DVD's with mixed AR's. Special features may not be 2.40:1, even though the feature is. Also, the focus may be different at the two extremes of the zoom range.


Vern
 

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Discussion Starter · #5 ·
I think it is very possible that the focus will not hold across the zoom. I will fly this plan by tech support with the PJ company (have a good contact). He will certainly know if the zoom will hold focus, etc. The focus change with focal length change may have to be a tweak on the "change-over."


I'll definately get a look at the projector before commiting too many assets.
 

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I do that with my lowly HS10. Zoomed for 2.35 will definitely show any problems with a DVD, but for most I find it acceptable. Of coure, viewing distance comes into play and you'll have to compromise on one AR vs the other. The HS10 has a 1.3x zoom, which is a little short of ideal, but comes close enough for me. I'll definitely never go back to not having a 2.35:1 screen, hopefully my next PJ will allow me a better quality experience, probably via an anamorphic lens.
 
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