Sony HS51 and 133" Screen

Quote:
The HS51 has a limited ANSI CR, so it is possible that what you are seeing is just the washout from bright parts of the image to dim parts through the HS51 lens. It could also be your room, but even with a perfect room you will be limited by what the HS51 is capable of.


That projectorcentral.com feature seems to use the marketing specs and not real world numbers, so I think it will actually do more harm than good. I find it kind of interesting that they reviewed the HS51 and claimed it was dim and said that a dark viewing space is more important than most projectors, but use a number that is something like 5x the lumens they measured to advise people about screens for it. Garbage in, garbage out. Or worse yet, garbage in, gospel out.


At 133" the High Power with low mount and SilverStar with ceiling mount are the only two I would be likely to recommend if a person was going to calibrate the projector (which results in lower lumens). That is, unless they just like their images dim.


--Darin

How much light does the HS51 output when calibrated ?


I have a 133" screen, matte white 1.0 gain. My projector is an Epson TW-100H which calibrated gives about 620AL. This gives med approx. 12 foot- lamberts which I feel is about perfect in my dark room (ok, the ceiling is white, but no outside light at all enters the room).


I read somewhere that the recommendation for movie-theatre brightness was 10-16 FL. I feel that's pretty reasonable and would probably be happy within that range.


Before, when I had a 80" 1.1 gain screen, I got 35 FL. That was way too bright for my taste and I had to use a filter in front of the lens to get the light-output down. I'd say I got about 25 FL which still was too much. Much more than 20 FL and I start to get a "TV"-experience instead of a "movie-theatre"-experience if you know what I mean. I also started to notice stuff like compression artifacs much more often.


So, from my personal recommendation, if the HS51 outputs between 600 and 1000AL I would probably be happy with a 1.0 gain screen if the room was properly darkened. More than 1000AL and I think I'd probably go to a 0.8 gain screen, buy a filter or reduce the light output if possble.


YMMW of course. If you like to watch a plasma TV at close range in a dark room you'll probably find the image too dim. I tried a plasma in a dark room and promptly got a headache...

Quote:
That dim ?


Well, you'd have the choice between a vutec screen then, or not using "cinema black" mode or whatever it is called.


My old TW100H is a light-cannon in comparisation then, at ~625AL calibrated


I'm waiting for the D5 1080p panels before I replace the TW100H. Hopefully there'll be a PJ available with good contrast and 700-800AL calibrated light output...

Quote:
The hi power is retro reflective. To get the best gain from it you should have the pj shelf mounted. If you have any light directly behind your viewing position it would be getting the max gain of the screen, and would lead to a washed out look!


check the HS51 and HS51 tweaks thread in the

vote in the "which pj did your HS51 replace poll" http://www.avsforum.com/avs-vb/showt...hreadid=511075

if you had not already done so.

Quote:
I am watching on a 106" screen today (Da-Lite High Power) and it is plenty bright. I think a material like the M2500, based on the samples I have, or the Silverstar would be too bright at this size.

Quote:
There are no lights on in the room. The only light is what is coming from the projector itself.


I think you are right about the screen being the issue, however. I am betting the problem is that, even with a flat black ceiling, I am getting enough light from the projector washing back over the screen from the ceiling that it is washing out the picture. I have several other material samples and they do not seem to have the same problem.


I am leaning to either going with a 133" using the M2500 material or staying at 106" and moving to Video Spectra 1.5.


Is there a tool you can get to measure brightness on the screen to get an accurate Foot/Lamberts number?

OK, here is what I have calculated for me screen needs. Can someone see if they can poke holes in this?


If I assume the calobrated Lumens of my projector is 350 (averaging between 300 and 400) and I want to get a screen brighness of 20 ft.l, I can go as high as 116" diagonal HDTV format with the M2500 2.5 Gain material. If I went with a 133", the projector would need to be putting out closer to 418 Lumens, which may be high.


From the reading I have been doing on this great forum, it looks like 16 ft.l is a great goal for a dedicated room. 25 ft.l is considered too bright by most. 20 ft.l seems like a reasonable compromise.


This leaves two questions:


1. Am I off my rocker here or does this seem reasonable?

2. How the heck do I determine how many Lumens my projector is actually putting out?


Thanks,


Shan

Damn this would be a whole lot easier if I knew what I was looking for.


I did some more playing around tonight and made a few interesting discoveries related to my problem (picture seems washed out).


First, this has nothing to do with lighting. I turned off literally every single light in the area, including items light under-cabinet rope lights, etc. No difference.


This has nothing to do with the retro-reflective properties of the High Power screen. My M2500 sample looks the same exact way. It is a brighter picture, but it still appears to be washed out.


This has nothing to do with screen size. I can unzoom the screen down to about a 85" diagonal screen and it looks the exact same, albeit smaller. Same difference if I zoom to the largest size screen.


The interesting thing is that the High Contrast Matte White fabric sample I have does not display this characteristic at all. Whether you refer to what I am seeing as a sheen or a washed out picture, you put that sample up there and the problem goes away entirely. The Video Spectra 1.5, High Power and M2500 screens all look like they are fighting with ambient light at all times, even though there is none to fight with, but the HCMW looks terrific.


The only issue now is what will the HCMW fabric look like when it covers the entire screen and is 106" in size diagonally? All of my calculations say it will be much too dim, around 12 Ft.l, assuming the projector is putting out 362 Lumens. But I think I am going to have to try it. I can buy a Model B with this fabric in the 106" size shipped for $200. I am beginning to think it will be worth the just to find out if it resolves my issue. Worse case, I end up with that fabric and a smaller screen.


The only thing that continues to baffle me here is why I do not hear others complaining about this issue. Surely it would bother everyone if all of the dark scenes on this projector seemed washed out. Confused.


Shan