which screen size should we get?

Honestly, I would get a Stewart Horizontal Electrimask Screenwall. This is a fix mounted screen that has top and bottom motorized masking. I use one and I purchased mine to start as a native 16:9 screen. This way it can be masked for 1.85:1 and 2.35:1. It is actually variable from 1.78:1 to 3.20:1. This screen is expensive, but well worth the money IMHO. Also you will likely want to use the GrayHawk screen material with a D-ILA projector.


Here's some pics of my frontwall...

Screen without masking at 1.78:1 (16:9)
http://personal.atl.bellsouth.net/at...rn/Screen1.jpg


Screen with masking panels lowered and raised for 2.35:1
http://personal.atl.bellsouth.net/at...rn/Screen2.jpg




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DMan
The Academy Home Theater

Thank you all for your responses. We have not purchased our projector yet. The reason we wanted the D-ILA was because we saw one being demo'd at the CEDIA Expo last September, and the picture quality (brightness and clarity) seemed significantly better than any DLP at the show. But we will definitely check out the Sanyo projectors suggested.


One question: Why is horizontal masking preferred? I was thinking, why not get a 2.35:1 screen and then 3 sets of vertical maskings to get 1.85:1, 16:9, and 4:3? Wouldn't this give us the largest picture possible in all the aspect ratios?


Also, what attributes of the Grayhawk screen make it a good choice for a D-ILA? Our installer suggested the MicroPerf with center channel behind the screen, but we are concerned that we won't be far enough away to not see the holes. Primary seating will be about 10-11 feet from the screen. Also, the room is not a dedicated theater. It is our living room, so ambient light and attractiveness of the whole setup are both concerns. We do plan to get a fixed screen.

Mark,


Yes, you are correct. For digital projectors you simply set the width and the top and bottom can be masked for the unused portion of the image (aspect ratio dependent). As you said and as I stated above, the screen that I use (horizontal masking) would be perfect for a digital projector.


What I was trying to convey was that Bjoern Roy uses a homemade screen method that he call's "constant area" by which he can mask on all four sides to create screen areas that are very close in surface area for both 1.85 and 2.35.

This is not the same as "constant width" (which is what I use) or "constant height". As far as I know, only CRT projectors allow you to do "constant area" since you can increase and decrease the image on both the horizontal and vertical plane.


Before I confuse you any further, check out the following post with plenty of pics for examples... http://www.avsforum.com/ubb/Forum4/HTML/002498.html




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DMan
The Academy Home Theater

Quote:
If you have not purchased the projector yet, why not consider other models. I would much rather have a Sanyo PLV-60, with native 9:16 display and a cheaper bulb that lasts longer. It has 1,200 lumens and produces half the heat as the JVC. http://www.projectorcentral.com/proj...m?part_id=1109


Or a Sano PLC-XP30 that has 3,000 lumens (uses the same bulb as the PLV-60), so you can watch movies with the lights on. http://www.projectorcentral.com/proj...m?part_id=1106

This is a great 3:4 XGA projector with digital inputs and, people say, a very good scaler built in. Either Sanyo model can be had for the same or less money than a JVC.

$6,000.-PLV-60, $6,900.-PLC-30 street prices. Either would work with a Stewart Gray Hawk screen.


Christopher

OK, fine, Bjorn is god. http://www.avsforum.com/ubb/wink.gif Now that we've got that fact established...


First off, darth maul, I don't think zooming on a digital projector gets you constant area. In order to do constant area as defined by Bjorn, you must be able to grow and shrink the vertical and horizontal dimensions of the image independently. Zooming will make the image bigger and smaller, but the aspect ratio of the width and height is maintained.


Secondly, based on DMan's suggestions and more research at ProjectorCentral (thanx to Christopher for pointing us there), it looks like we may go with a 4:3 screen with horizontal masking. We will be installing the projector in a console/coffee table unit because the room constraints make both back wall installation and drop-down lift options unfeasable. The shorter throw distance forces us to go with the D-ILA S15U, which does not have a zoom lens. The D-ILA has a native aspect ratio of 4:3, so to maximize the number of pixels used for each display aspect ratio, it makes the most sense to mask horizontally from a 4:3 screen.


Fortunately, because we don't have installed dedicated theater seating, our viewing distance can be flexible. We can simply move our chairs forward or back to compensate for the different image sizes.


The last concern would be the noise and heat generated by the projector especially because it will be in the middle of the room, but that's a topic for a different forum...


What do y'all think?

"First off, darth maul, I don't think zooming on a digital projector gets you constant area. In order to do constant area as defined by Bjorn, you must be able to grow and shrink the vertical and horizontal dimensions of the image independently. Zooming will make the image bigger and smaller, but the aspect ratio of the width and height is maintained"


We are talking about finished viewable image right? Sure you can get constant area by zooming. Ya, the inharent problem with a 4:3 projector is that for watching different aspect ratios you will be losing 1/3 of the image resolution or more. But certainly you can still do a constant area for the projected image on a screen. No, not like a CRT, which uses its full resolution for the various aspect ratios, but its still constant _area_. And I guess I define constant area, as the same square footage of viewable material not including any black bars for each aspect ratio.

http://www.avsforum.com/ubb/wink.gif If you say I can't get a constant area with my LCD projector, fine, but then what do I have set-up in my living room? http://www.avsforum.com/ubb/wink.gif

Mark,


No problem!


Kam,


I agree completely. Unless Madoka wants to use this projector as her main television for 4:3 viewing, I would suggest going with the 16:9 screen as well. But a 4:3 screen with horizontal masking would be an equally pleasing alternative.


Enjoy,




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DMan
The Academy Home Theater

Madoka,


10-11' is right at the distance that the perforations start to disappear, at that point they are very small and almost undetectable. If you are considering perforations and your closest seating is in that range you should probably obtain a sample from Stewart for evaluation to see how it looks to your eyes. Hopefully you will find that even if you can see the perforations at that distance they are not objectionable (that was my opinion when I was evaluating my micro-perf sample).


Stewart custom manufactures all their screens, there should be no cost penalty for getting the screen size and aspect ratio you want. If you watch a lot of movies, I would echo DMan's recommendation and recommend a 16:9 screen with horizontal masking. Unless you plan to use this as your primary TV I would not recommend a 4:3 screen, your ceiling height may limit the size of screen you can use at that aspect ratio.


The S15 may not work for your application, it is designed for rear-projection and the lens must be even with the centre of the screen, you may want to consider the M15 (I believe it has a shorter throw than the G15 and it has a zoom lens). You may also want to consider the new 150HT, it is much better out-of-the-box than the regular models and it comes pre-calibrated. Fan noise is also reduced and it has interchangeable lenses.


Regards,


Kam Fung

Hi All,


Thanks for all your comments and suggestions thus far.
Quote:
Quote:
Can you gentlemen please elaborate on why you recommend the 16:9? I would definitely agree with you if the projector throws a 16:9 image. But the D-ILA projects a 4:3 image. So we thought it would be best to go with a 4:3 screen since that would maximize the number of pixels used for each aspect ratio. What advantage would a 16:9 screen offer to make sacrificing maximal pixel usage worthwhile? Are there other important factors we have not considered? FYI, we would not have problems with wall height for a 4:3 screen since the room has high ceilings. We are aiming for a 8' wide screen.
Quote:
Sigh... So the S15 won't work. It was our best bet at a 1:1 throw distance. Both the M15 and the G15 takes 50% offset from center projection, but the M15 has a 1.5:1 throw distance to screen width ratio and the G15 is 2:1 to 3:1 with zoom. Given an 8' wide screen, both of these would put the projector too far back in the room.


The 150HT sounds intriguing, but we couldn't find good specs on it on either ProjectorCentral (only minimal info there) or the JVC site (not found at all). Can you recommend another site where we can find specs on this unit?



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Madoka


"Winners never quit, and quitters never win. But those who never win AND never quit are idiots."


[This message has been edited by madoka (edited 07-03-2001).]

Madoka,

Yes Bjoern is near God status but there are at least 12 others who qualify so he cant get a swelled head.

I noticed nobody stepped up to advise you on sitting right on top of PJ with loud fan noise and enough heat to save on fuel bills.Hush box adds ventilation issues.

You may also be around 12FL with grey screen in living room with lots of ambient light to deal with.This number comes from the Bill Cushman measurements in WSR on G-20 PJ.

He says he wants 50-100FL under these conditions.

Hopefully members who have dealt with these issues will be giving you more advice.

Regards Ron
http://www.avsforum.com/ubb/smile.gif


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Ron

"Your priorities will be different-its the weighting that counts!"

Quote:
If ceiling height is not a problem, then you might as well go with a 4:3 screen. The reasons for getting a 16:9 in most installations with a screen of that size would be ceiling height and cost. An 8' wide 4:3 screen is 6' tall and in a standard 8' ceiling, depending on how your seating is arranged, there may be sight-line problems (people's heads getting in the way) and problems fitting the centre speaker in the remaining 2' under the screen. You also lose some height from the frame/motors that are associated with the screen. A 16:9 screen would be much shorter in height and would generally give you more flexibility in your installation, but as you say, you would have problems with 4:3 material. That is why we asked if you were watching primarily movies on that screen (and 4:3 on another TV). The cost for a 16:9 screen of the same width is also less than a 4:3, if that is a concern. (I assume it's not if you are considering a horizontally-masked Stewart!)

Quote:
Have you considered suspending your projector from the ceiling? What kind of ceiling do you have and how high is it? What size of room do you have? Many installations with those kinds of issues end up with projectors attached to a pole off the ceiling.


The 150HT is a new model that JVC was showing at INFOCOMM a couple weeks ago, I don't know when it will start showing up in stores, but hopefully it will be in the near future. It costs quite a bit more than the regular G15, but it requires a lot less tweaking to get a stellar image. I am not surprised there is not a information out yet, but it is very similar to the M2000 except with 1500 lumens and less noise. The lens options are the same as the G15, M15, S15 so you are still in the same situation with regards to throw distance.


Regards,


Kam Fung