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Discussion Starter · #1 ·
Most of the content I watch (on my Media Center PC) is 16:9. The stuff that isn't I almost always set to Zoom 4, which to my eyes is the best compromise between zoom/stretch for 4:3 content on my 16:9 screen.


I think I have got the wife convinced to let me build a theatre room if and when we make extra bedroom additions to the house (it all hinges on if the baby-to-be-named is a girl or not
). I expect to spend a good bit of money on the addition and theater stuff, but I'm also trying to balance it out with common sense.


So as "cool" as a four-way masking setup would be, if I'm happy with zoomed 4:3 content, wouldn't simple two-way vertical be perfectly sufficient for my needs? I'm hoping to do a ~144" 16:9 screen and then just mask it down for 2.35 and 2.40 content. I figure 4:3 will eventually go the way of the dodo anyway, so no worries, right?


EDIT


Okay, so you guys have pretty well convinced me to go with a 2.4 native AR screen plus lens setup. Obviously this is going to require side masking.


Looking at all of the DIY side masking projects, I really don't know if I like the cable/pulley setups. I think one could make up something a little different and keep noise down.


To that end, I'm thinking about doing something completely different and possibly insane. I'd like to have cam-driven side masking. I'm envisioning a disk mounted on a motor (potentially inside of an MDF box to make it even quieter) with a rocker switch mounted to ride on the disk surface. An extension arm will mount to the disk on one edge with a swivel bushing, stretching out to a T-bar with another swivel in the intersection of the T. To keep things perfectly vertical I think there might be a need for races on floor and ceiling.


Now, with the disk at 3:00 the side masks will be fully shut, leaving the screen at 4:3. Detents can be added to the surface of the disk to actuate the switch and interrupt the motor at various points. The advantage to this is a large range of size tweaks - 4:3, 16:9, 2.35, 2.4, whatever, with something as simple as a piece of ballpoint pen to flick the switch and break the relay. I could probably even hand-crank it to match some of the strange aspect ratios of older movies and add extra stop points.


In doing this the motor only has to turn one way; after it reaches 9:00 and full extension and begins to return, the masks will close again. I can make the circuit REALLY simple and just have the IR signal act as on/off. So if going from 4:3 to 2.4, you'd send three on pulses. That's easy enough; I can program macros into my Harmony of 1-3 pulses, with pause buffers long enough for the disk to reach each stopping point.


I think this has the potential to be a great deal quieter than a pulley and cable system. Given that there are only two points of actuation per masking panel (and potentially any noise from the races, but Teflon bushins could be used there as well.), there's not as many opportunities for noise. And, as a side bonus, I don't have to worry about hiding cables running above and below the screen.


Thoughts?
 

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That is what a lot of folks do in order to have the biggest 16:9 screen possible and then still have the same width for 2:35 screen. Often it is done when you have width contraints in your room and still want a big impact with 16:9.


If you dont have width as a constraint you can still figure out the largest 16:9 you can fit or feel comfortable with, which will give the height you want and then get 2:35 screen accordingly for CIH (constant image height) with that height. This way you only need a one way masking solution as well but rather one that comes in from the sides. This way you can still get a system which can handle 16:9 as well as 4:3.


New programming for 4:3 will probably go away, but there are older classics which you might not be interested in now that you may develop an affection for later on.
 

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Discussion Starter · #3 ·
Doing it the other way, wouldn't I also need a lens, though?


Width really isn't an issue, the room isn't built yet so I can make it as wide and as long as I want to; but I'm also trying to keep costs relatively reasonable. Spending ~$1000 on a lens might be great and all, but I could also buy flooring, a popcorn machine, and possibly build a screen for that much. I suppose it might be cheaper to do side masking rather than upper and lower, but enough to justify, at bare minimum, a G for a lens . . . . not sure.
 

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Not necessarily,


You have a couple of cost effective options. My man Jamis an AVS regular and recently featured on electronic house did what I described with the biggest height you can with 16:9 and then figured his 2:35 from there.
http://www.avsforum.com/avs-vb/showthread.php?t=1170096


He uses the Panasonic 3000 and uses the zoom method to eliminate the top and bottom black bars. He doesn't use masking for 16:9 at the moment as he doesn't find it bothersome enough. Personally checking out his setup it was top notch and he can switch aspects at the press of a button.


Your other option is a DIY lens you can either use trophy prisms or Surplus Shed prisms to make your lens. I spent about less than a couple of hundred bucks making my own lens with Surplus lens' which are very nice prisms with anti reflective coatings on the sides.
http://www.avsforum.com/avs-vb/showt...0#post14908500


The performance I get from them is very good. I had some forum members at my place this past weekend and everyone seemed pleased with the image it threw.


The only caveat with Suplus prisms is that they are small so you have to make sure they fit with your projector before committing
 

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Don't be discouraged it's a lot to take in and can easily become overwhelming. It sort of depends on how handy you are and what you are williing to try. Another factor is the quality level you are seeking. Trophy prisms have a good amount of CA (Chromatic Abberration) (spelling ?). The Surplus prisms are better at taming this.


Your cheapest manufactured lens with better optics and corrected CA is going to run you about $1,500.00 or more depending on who you go with, unless you find something used.


Don't worry though you could start off with a zoom projector and add a lens later if you desire to. New projectors should be getting introduced this fall and I'm sure some will follow suit with what Panny is doing. Just be sure to get a projector that offers vertical stretch so you don't have to worry about that from another device if you end up going with a lens or plan to in the future.
 

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Discussion Starter · #7 ·
Yeah, I was looking at the Aussiemorphic thread and thinking, "Hmm, well, I could save up that much lunch money in the next year or so."
Then I was looking at the 5x12 Wilsonart panels and thinking, hey, that's 2.4 . . . all I need is a projector that does vertical stretch, a long enough room, and I'm set.



Mask the sides for 16:9 and 4:3 zoomed with the lens slid out of the way . . . slide it in place, kick in the stretch and open up the curtains . . .



This place is just evil. Evil evil evil.
 

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Once you are bitten there is no going back.
 
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