CurtPalme.com Home Theater Forum

[walteritaly]

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Hello everybody,

I would like to build a 16: 9 110 " screen for my marquee 9500, now I am using a neutral 1/1 gain screen and
I would like to increase the reflection of light and also the contrast,
I have seen that there are more or less dark gray sheets on the net that increase gain and contrast, for this reason the contrast is less affected by the lighting of the room.
I've also heard of black screens that increase these factors a lot.

Is it possible to make a CRT projector work properly with this type of screens or should I stay on a neutral screen as much as possible?
What do you advise me to do?

thanks in advance.
Walter.

[nidi]

Walter,

go with a higher screen gain of at least 1.3.

it will be too dark with a neutral gain screen.

I've been using a Stewart StudioTek 130 for almost 20 years now and still am super happy with it.

if you watch older 4:3 movies from the 30's up to the 50's , consider a 4:3 screen as BluRays with those movies
can be made to use the full 4:3 phosphor area which gives you higher lightoutput.

[walteritaly]

[spoonsight_BG808s]

Hi

I have a Seymour screen excellence Ambient-Visionaire 2.1 Gain, 130 inch 2.35:1/cinemascope curved screen and it is a great screen. No sparkels/sheen and no hotspoting. I use it with a Runco DTV 1200/Barco Cine 9 and have 13 Ftl without driving the projector hard. I have samples of most of the serious brands and this is by far the best I have seen with a CRT projector. One of the best calibrators in Norway have also seen it and would not use any other screen with a crt.

With my Jvc digital projector it can be a bit aggresive and you can see some amped up effect/sheen, but then we are talking 40 - 100 ftl.

Contact seymourav.com and Jon/Dan will send you some test samples. Some of the best consumer service I have experienced.

[garyfritz]

How did you curve it? Good that you did, because a 2.1 gain would definitely hotspot badly with a flat screen. I even notice hotspotting on my 1.3 screen.

40-100 ftl on a 130 inch screen !?? What kind of a light cannon are you using??

[walteritaly]

[walteritaly]

[spoonsight_BG808s]

Hi Gary
I did not curve it myself, used a curved frame and attached the screen with zip ties:)
The Jvc is a X5900 in europe, not sure what its called in in the States. The lowest Ftl I can get on my 130 inch screen are 24 ftl, low lamp and iris -15. Remember 2.1 real gain on the Seymour screen.

To Walter
Two friends of mine have the same material in flat screen, 92 and 110 inch if I remember correct. There will be a little hotspoting if you do not have the correct throw distance, think it is 1.8 times the width of the screen. I have 1.5 distance on my curved screen and that works fine. You could also use contrast modulation to even things out.

[garyfritz]

The x5900 is rated 1800 lumens -- less than I expected for your ftl. That's about 40% more than the 1300 of my RS45, which I run on a smaller (100" diagonal) but lower-gain (1.3) screen. ftl = gain * lumens / sq-ft, and my screen is about 28.5 sq ft. So my ftl at full lumens should be 1.3 * 1300 / 28.5 = 59 (!!??) -- which is much higher than I see. I assume I have the iris clamped down. I think I read about 20 ftl the last time I checked.

Your 130" (diagonal I assume) 2.35:1 screen is about 42.4 sq ft, but it's 2.35:1 while your projector's panel is 16:9. If you use an anamorphic lens, you benefit from the full 1800 lumens of the panel. If you don't, then your 2.35:1 image displays on the middle of the screen, and you lose about 25% of your light-emitting area. So if you don't have an anamorph, your effective lumens are about 1350.

Assuming you have an anamorph, and with your 2.1 gain (from which you get full benefit due to the curve), you should have a full-brightness rating of 2.1 * 1800 / 42.4 = 64 ftl, or about 48 ftl without anamorph. So yeah, you would really have to crank it down to get down to 24 ftl --- about the same as me.

[spoonsight_BG808s]

Hi Gary

With a curved screen you also get a 10-20 % light boost (dependent on curvature of screen) when the light is more centered back at seating pos. This will not show up in readings with a spectro/colorimeter.

[walteritaly]