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Posted By: JLunden 2.35:1 DIY screens? - 12/20/05 08:06 PM
I've seen a few people on this and other boards that have 2.35:1 screens. I'm wondering how this is done. I know with my Z2, I'd have to constantly be adjusting the PJ between 1.85 and 2.35 because the 2.35 would have to be larger on the screen. What’s the benefit of doing this? You seem to be trading thinner black bars for much larger bars on the sides for 1.85 films. Am I thinking about this wrong?

-JL
Posted By: snakeyes Re: 2.35:1 DIY screens? - 12/20/05 10:57 PM
Hopefully Randy (Sirquack) will be by to explain this i think he even has the same projector your talking about. im not sure if that is the format his screen is in but i belieive he can point you in the right direction.
Posted By: SirQuack Re: 2.35:1 DIY screens? - 12/21/05 04:57 AM
I would recommend you check out the 2.35 forum on AVSforum to get the full background, but I'll try to help a bit. When watching 2.35 movies on a 16:9(1.78) screen, as you know, there will be black bars on the top and bottom. As a result, 33% of the panels (pixels) are not being used.

To resolve this you must first use a scaler to vertically stretch the image to fit the height and reclaim those lost pixels, but leave the width alone. This will make everything look skinny. Many people use HTPC's with theatertek software to perform the scaling, however some projectors and DVD players will also achieve the needed stretch. A benefit of using the full panel is that you will increase brightness by as much as 20%or more.

The next step is to reshape the stretched image into the needed 2.35 aspect ratio, to fit your 2.35 screen. This is accomplished by using an anamorphic lens. Prismasonic, Panamorph, and ISCO are the most popular brands. There are vertical and horizontal type lenses. I prefer the horizontal types as it takes my image and horizontally stretches it back out to fill my screen. I can achieve a huge image from a relatively short throw distance. Vertical lenses basically do the same thing, however, they vertically squeeze the scaled image back down to create a 2.35 image and a smaller screen from the same throw distance.

I have a Z2 and a Prismasonic H600 lens and I will never go back to 16:9 screens. There is nothing like enjoying movies as they were intended to be watched in the theaters.

This is called a constant height setup. The height stays the same always, the only thing that changes is the width. It is much easier to mask the sides for 1.85 and 1.33 material, than it is to mask the tops of the screen, just use curtains like they do in the theaters.

Now the Z2 will only vertically stretch 480p material, however, the newer Z4 will perform the needed stretch on 480p, 720p, or 1080i, so I've got my eyes set on the Z4 at some point. There are other projectors that will do the needed stretch, as well as DVD players, and high end scalers like DVDO or HTPC's.

Here is my screen image size for various movies:

2.35 material - 51" x 120"
1.85 material - 51" x 94.35"
1.33 material - 51" x 67.83"

A few pics

1.85 movie "Napoleon Dynamite"

2.35 movie "StarWars Episode II"

Posted By: sonicfox Re: 2.35:1 DIY screens? - 12/21/05 05:30 PM
Hey Randy! This is OT, but this is the first time I've visited your website. Any chance that you might be able to provide updated pics of your theater all furnished and everything? Even from the pics on the website, I can tell it's got to be really nice!
Posted By: SirQuack Re: 2.35:1 DIY screens? - 12/21/05 05:31 PM
It astually is not finished yet Sonic, no carpet yet, and still attaching trim around the floor area. Hope to get a lot done over the Xmas holiday's...
Posted By: GregM Re: 2.35:1 DIY screens? - 12/21/05 07:24 PM
One very important thing to point out is that the anamorphic adapters often run $1,000 or so. I would rather put that into a new PJ or M60Ti's than a CH setup. Yes I would like the ultimate viewing experience that this offers, but unlike a new PJ or speakers, I would only gain with 2.35 movies. I just watched Charlie and the Chocolate factory and it was a 1.85. If all movies were 2.35 I might make the move but for now, I can't afford it.

Not trying to downplay CH as it certainly is the way to go, but it does cost quite a bit of money.


Greg
Posted By: SirQuack Re: 2.35:1 DIY screens? - 12/21/05 08:03 PM
Actually, you can get a Panamorph for $495, a Prismasonic for 700-800, and ISCO being the most expensive.
Posted By: GregM Re: 2.35:1 DIY screens? - 12/21/05 08:14 PM
Sorry about the price snafu. When I checked into the CH thing a couple months back, I was under the impression it would be $999 minimum. Nice to see it isn't so pricey.

Greg
Posted By: SirQuack Re: 2.35:1 DIY screens? - 12/21/05 08:21 PM
There is also the DIY route some people have actualy built there own anamorphic lens. I built my screen and projector mount and that was it...
Posted By: JLunden Re: 2.35:1 DIY screens? - 12/21/05 10:00 PM
Does all this stretching not kill the picture quality? I mean, the Z2 can only do so much. If I zoom the image with the Z2 it doesnt look as good as it does when on normal 16x9 mode. Do the scalers make up for this?

Thanks
JL
Posted By: SirQuack Re: 2.35:1 DIY screens? - 12/21/05 10:13 PM
If it killed the picture quality I would not be using it.... I don't like the Zoom phrase. On some DVD players zoom actually stretches the width and height, which is not what your doing here. You are leaving the width alone, and stretching vertically to fill the unused 33% of pixels that are lost when watching 2.35 material on a native 16:9 projector. The lens then reformats the movie to fill your 2.35 screen. Also, I"m not talking about the zoom on the lens, but the zoom menu option. AVSForum is really the best place for information....
Posted By: SirQuack Re: 2.35:1 DIY screens? - 12/21/05 10:16 PM
A few links:

http://www.panamorph.com/Overview.html

http://www.prismasonic.com/english/intro.shtml

http://www.avsforum.com/avs-vb/forumdisplay.php?f=117


Posted By: JLunden Re: 2.35:1 DIY screens? - 12/22/05 05:54 PM
Thanks Sirquack!
I'm still not sure I entirely understand, but I'm getting there.

Don't be surprised if I hit you up for some advice in the near future.

Thanks
JL

P.S. Did you make the FOXesque logo on your site? I really like it!
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