CurtPalme.com Home Theater Forum

[Aesclepius]

Hello all,

I am hoping to tap into your experience for guidance about a projector screen purchase. I am building a dedicated home theater in my basement, which should be a near-completely light controlled environment (walls painted dark burgundy, furniture and fixtures all dark burgundy/black, and only 1 window with a black-out shade.)

I own a Panasonic PT-AE8000U projector, which will be ceiling mounted 15 feet from a 119” diagonal screen. Based on real-world performance reviews, I think this projector will generate about 620 lumens on its “best” mode: Rec-709. I think this should create an image brightness of about 14.8 ft-Lamberts on a 1.0 gain screen in my darkened theater.

I am concerned that 14.8 ft-Lamberts does not provide much wiggle room for adding in ambient light (I would prefer to have side sconces dimly lit while watching some movies), or in case of projector lamp fading over time.
My goals are like everybody else, I guess: to have an acceptably bright image with good color saturation and the deepest blacks possible.

My question is: in order to increase the image brightness a bit, would it be better to use a matte white screen with a brighter picture mode on my projector, or to purchase a higher-gain screen from the beginning, such as a 1.3 – 1.4 gain screen. I have at least 2 brighter modes to choose from on my projector (up to around 1800 lumens on “dynamic” mode,) but my understanding is that increasing projector brightness will lead to more washed out blacks and inaccurate colors as well. I have already experienced the “dynamic” mode projected onto sample screen swatches, and the blacks were definitely washed out in a pitch-black basement.

Would using a higher gain screen allow more wiggle room for image brightness while maintaining deep blacks, or does increasing screen gain lead to washed out blacks as well? My seating will be in a relatively narrow viewing cone, so I think the narrower viewing angle of a higher-gain screen would not be a problem.

My frustration with this screen selection process is that I have no local dealers to demo various screen types, and of course demos would not apply directly in my particular room, but I don’t want to make a bad decision about a screen. I’m hoping you all can use your real-world experience to guide me.

Of course, it also occurred to me that maybe any of the above options would look excellent for a non-videophile movie lover such as me, and maybe I’m overthinking this.

Thanks in advance for your help!

[kal]

Welcome to the forum!

[kal]

Welcome to the forum!

[CIR Engineering]

Different modes in the projector that are designed to "improve" the image will always cost you in the image quality department. In an ideal theater room, your best bet with the projector is to calibrate it and forget it.

Using a screen with a 1.3 gain will not hurt your image quality at all. 1.3 is low enough of a gain where its distortion is literally invisible from the viewing distance. As you go above 1.3 gain you will distort the image more as the gain gets higher (hot spots and color uniformity). However, lots of people don't mind a little trade off.

Keep in mind that raising the gain of the screen will also raise the black level with it. So the higher the gain, the higher your black point.

craigr

[Aesclepius]

Thanks for your responses!

Kal, I am thinking that if I am watching a movie with my wife, we are glad to have the lights completely off for best image quality. However, if our young children are watching an animated film, or if we have guests over, we may want to keep just a little ambient light to make it easier for guests to move about the unfamiliar space, etc. I was thinking that side wall sconces that are dimmed significantly will hopefully not cast too much light on the screen.

CIR, it's good to hear your perspective that a 1.3 gain screen will not cause any image quality loss. I was thinking about the Carada Brilliant White material, which from what I understand is somewhat less than its advertised value of 1.4 gain. Just for clarification, when you say "raising the gain of the screen will also raise the black level with it," do you mean that higher screen gain results in blacks that are less deep and inky (more light or gray), or do you mean that higher screen gain allows more inky blacks? Sorry for the naive question!

[garyfritz]

I have a Wilsonart Designer White screen, which has a measured gain of about 1.25. I very definitely notice color issues on mostly-white scenes -- there's a bit of a hot spot and I see some blue/red colors that shouldn't be there. It's fairly subtle but I see it. It's definitely different than my previous ~1.0 gain blackout-cloth screen.

If you use a 16:9 screen, it'll be about 104" x 58". That's 6067 sq in = 42.13 sq ft. 620 lumens / 42.13 sq ft = 14.7 ftL, so you've got that figured about right. 15 ftL is a nice bright image -- much brighter than most of us see with our CRTs, since the digital will deliver 620 *ANSI* lumens vs. the 225-250 ANSI lumens we get out of most CRTs. (Most CRTs are rated at 1000-1200 *peak* lumens, but that only applies to small bright areas.)

Given the lumens you've got, personally I'd go with the 1.0 gain screen. Then you'd be sure to not see any color artifacts.

Sconces on the side walls during kid movies are no problem. The kids probably aren't terribly discerning videophiles. Keep it dark when you want to appreciate the best picture and it's all good.

[kal]

[kal]