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Discussion Starter · #1 ·
I have done more research on screens than I care to remember and I'm more confused now than when I started. I have noticed that the raves on HP screens are pretty consistent. I have seen also that there are limitations. My room is dedicated and the walls and ceiling are dark. I would like to use a

54"x126" (138" diag.) screen. My ceiling is 94". The depth of the room is 220" and the width is 176". My eye height while viewing is 37" and 170" from the screen.The width of my seat is 70". I have a JVC DLA HD750 projector which I would like to mount on a shelf suspended from the ceiling. I would like it high enough not to be a hazard or a distraction. Can I use an HP screen? Can anyone suggest a screen that's going to make me happier than the proverbial pig?
 

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I really like the High Power screen.

Get the projector as low as you can without being a hazard and you too will really like it.


(All this was until I went to an Acousticlly Transparent screen. I tried but could not go back, even though I like the MATERIAL of the high power better)


Scott
 

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Why not mount the pj on/behind the back wall where it will be out of the way and harder to hear?


I also recommend the HP; I've got one and an RS1.
 

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Discussion Starter · #4 ·
FLBoy has said in his posts that the projector should be as close to eye level as possible.I can mount on back wall but projector will be approximately 9" from ceiling.
 

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HP has requirements if you want it to work to it's fullest potential. That is, viewing needs to be withing the viewing cone. Ceiling mount more than a couple of feet over the viewer is not going to get you much gain. If your environment and projector placement is correct, it is the best thing since sliced bread, if not, then look at other types of fabric. Tryg's review spells it out in all the gory detail.
http://www.avsforum.com/avs-vb/showthread.php?t=773065

Difference between 2.4 (new HP) and 2.8 old HP the one tryg reviewed
http://www.avsforum.com/avs-vb/showthread.php?t=1213577
 

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Quote:
Originally Posted by HWF-1 /forum/post/18313371


FLBoy has said in his posts that the projector should be as close to eye level as possible.I can mount on back wall but projector will be approximately 9" from ceiling.

Mine's 12" from the ceiling, works great.


Though I only get a gain of about 1.6, it beats the heck out of 1, and I get all of the other HP advantages.


Use FLboy's calculator http://www.avsforum.com/avs-vb/showthread.php?t=966057
 

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Since my name is being bandied about here, I thought I might as well jump in.
I want to encourage the OP to strive to get all the gain that the HP can muster. Here's why.


A 54" x 126" screen is 47.25 sq ft. That's about 60% bigger than my 100" 16:9 screen and will produce about 62% of the brightness, all else being equal. My seating arrangement gets me a calculated center screen gain of 1.8 from my HP screen. When my RS10 was new, I decided that the middle setting of the lens aperture gave me my preferred level of brightness. My PJ now has 400 hours on the lamp. Last night I determined that the wide open lens aperture setting is what I prefer now. I'm currently running the lamp power on Normal (low power), so when the lamp ages further, I can switch to High to restore my brightness a second time.


My point is that it is a good idea to start with a screen size and gain that do not force you to run the PJ "flat out" in the beginning, unless you don't mind having to buy a lot of expensive projection lamps. Of course, with the HP you can start with the PJ in a high position and then lower it as the lamp ages, but that is best planned for in the beginning.
 

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Discussion Starter · #8 ·
FLBoy I was not bandying your name about, it was hero worship. Using your gain calculator I get a gain of about 1.37 and would think that I could get an angular reflective screen of about the same gain. This would not restrict my viewing angle as the HP would. Your mention of having to use the bulb on high has given me something to think about. I may even consider reducing my screen size a bit.
 

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"This would not restrict my viewing angle as the HP would."


I'd check the specifics of the screen w/your setup before saying that.


Even if you get more gain with the AR (angular reflective), its brightness variation will be more noticeable than that of the HP.
 

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HWF-1: I am curious about your resistance to lowering your PJ to a level more suitable for the HP, because I think the HP would be ideal for you if you want to go large and wide. Is the PJ above a narrow traffic pathway that you don't think you can change? Is a pedestal mount or a ceiling mount with extension pole not possible? Is this a WAF issue? Just curious, if you don't mind my asking.
 

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Discussion Starter · #11 ·
The PJ would've been directly in the entry pathway. Looking at it again I could move the projector forward so it is almost directly over the seats and use an extension pole to lower it to about 20" from the ceiling. Then the seat would prevent anyone walking into it. I haven't turned my projector on yet, but I understand it is very quiet, so sitting under it should not be a problem. I'll have to work on putting it on a suspended platform because I want to add an anamorphic lens in the future. Thanks for mentioning the extension pole. See, you are my hero.
 

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"The PJ would've been directly in the entry pathway."


What about moving it sideways - the HD750 has horizontal lens shift.
 

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Quote:
Originally Posted by HWF-1 /forum/post/18321619


The PJ would've been directly in the entry pathway. Looking at it again I could move the projector forward so it is almost directly over the seats and use an extension pole to lower it to about 20" from the ceiling. Then the seat would prevent anyone walking into it. I haven't turned my projector on yet, but I understand it is very quiet, so sitting under it should not be a problem. I'll have to work on putting it on a suspended platform because I want to add an anamorphic lens in the future. Thanks for mentioning the extension pole. See, you are my hero.

Ah, yes, always at the ready to rescue a damsel in distress!


Seriously, moving the PJ forward is an excellent idea in your situation, because it will be brighter at short throw, and you will need all the brightness you can get. While you are initially using the zoom method of CIH, keep in mind that you will need about a 15 foot minimum throw distance for the HD750 to fill a 126" wide screen. (The minimum throw distance to fill the 126" screen will shrink to about 11.5 feet after you add the anamorphic lens.) Both of these minimum throw distance figures include about 6" of added distance for adjustment purposes.


The HD750 is very quiet, but it does exhaust hot air downward and to the right from the screen viewers' perspective, so just keep that in mind when placing the PJ so you don't become a hot head.



"What about moving it sideways - the HD750 has horizontal lens shift."


True, but be aware that if the viewers are seated square to the screen, the "sweet spot" of the HP will skew to follow the PJ lens, and the PJ side of the viewing audience will see a brighter image than the non-PJ side. Unfortunately, horizontal lens shift will NOT compensate for this particular effect, so you would not want to move the PJ very far sideways IMHO.
 

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"The minimum throw distance to fill the 126" screen will shrink to about 11.5 feet after you add the anamorphic lens."


Assuming he gets a horizontal expansion vs vertical compression lens.
 

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Discussion Starter · #15 ·
I not a damsel, just a dirty old man. I think my problem is solved. I thank everyone who particated and helped and really appreciate the kind tenor of the posts, unlike some I have seen that are downright nasty. Thanks again.
 

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LOL. You fooled me with your "hero" thingy, DOM. Good luck with the new system. Please let us know how it works out.
 

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Quote:
Originally Posted by FLBoy /forum/post/18330978


LOL. You fooled me with your "hero" thingy, DOM. Good luck with the new system. Please let us know how it works out.

Haha, I assumed the same from the name, I figured HWF stood for Hot White Female!
 

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Discussion Starter · #18 ·
WOW! Didn't mean to get you guys going. Time and a fertile imagination can create wondrous things.
 

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Discussion Starter · #19 ·
Don't know how to do the Quote thing. In earlier posts both "FLBoy" and "noah Katz" refer to throw distances of 11.5 ft with an anamorphic lens. I've tried the Projector Central calculator and can't seem to get to that figure. Ive got an HP screen 54" high x 126" wide. Got my screen up, ready to hang my projector. Please help. Thanks.
 

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Since someone mentioned lens shift can someone explain how does it affect gain for the HP? I can't get my head around it. If your seating position is fixed in the middle what effect on gain would the placement of the projector to high right corner for example compensating with lens shift have?

Is the light always bounced back to exactly the middle of the lense no matter how far up/down, left/right the projector is placed?

So if you have a 3 seater couch and the projector is placed far right and up will the person sitting on the right get a brighter screen?

I don't understand what part angles play in this scenario. I hope the question is somewhat clear.

Even on my 3 seater couch the left and right seat is under half the brightness of the middle seat. Is this what everyone is getting on the HP?
 
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