Hi Power Blacks=Grey?

Remember the HP reflects light back to where it came from. For a viewer sitting under the PJ the reflections from side walls will have minimal impact on the screen, the wall behind the viewer is a different matter. This does not mean that light walls, ceiling and floor will not degrade the experience, just that it will not be directly washing out the screen image.

The strengths and weaknesses of the HP have been discussed at length, below are the hight points from my playing with a sample and summary from reading on the subject.

The HP will elevate blacks, not hotspot, no sparkles, accurate color, immune to waves, has a noticeable viewing cone in short rooms, likes but does not require the PJ to be placed just above the viewers head.

I would suggest that before going with the HP you should make sure that from all seating positions in the room it has enough "pop" left. From the two ends of my sofa at 13 ft from the screen the HP sample had about the same gain as the BOC it would have replaced. Kids on the floor would not have had much to watch.

In the right room it is great, just make sure it does what you want from all positions in your room, not just the #1 and #2 chair.

Best I can tell mother natures "processing/perception" make all the measuring a bit of a game anyway. What the brain does with black levels, brightness, contrast, and preference is very complicated and makes picking a screen somewhat subjective.

I ended up with a SMX AT screen. Really am sold on having the sound come from behind and not under/beside the screen. Personal preference.

What you like the best is what will be the best for you to install.

"The HP will elevate blacks"

This implies that it lowers contrast, which it does not.

It's the same as using a smaller screen or brighter pj w/same CR.

The new walls won't help.

The HP is a 2.8 gain screen. This means that the level of everything is increased.

In the case of blacks, an HP screen will have a level of absolute black three times higher than a neutral gain screen of the same size with the same projector.

To get a deeper level of black with the HP, you'll need a bigger screen or a Neutral Density filter.

So the choice is yours. The HP will maintain CR and give a very bright image that many love. The downside is that your blacks will be higher than a similarly sized screen with less gain.

How big a screen are you thinking?

Right, flat. You don't want it to shine. And dark walls and ceiling will improve your black level and ANSI contrast to the extent that they reduce secondary reflection of light originating from bright areas of the image back onto the dark areas of the image. In a completely black environment, your ANSI contrast will be that of the PJ, and will be unaffected by the type of screen. Obviously, black (and white) levels will be affected by the screen gain.

As to the gain of the HP, 2.8 is higher than you will be able to obtain in a real-world installation. Sure, the gain peaks at 2.8 when the error angle (i.e., the difference between the projection angle to a point on the screen and the viewing angle to the same point) is zero. But the only way to obtain zero error angle would be to place your head inside the projected beam, which would block some or all of the beam, or to sit directly behind the PJ with your head at the same level as the PJ, which would block your view of the screen. In a practical installation the HP can deliver a gain of about 2.0 or slightly more to the "best" seats. (You can use my All Screen Gain Calculator to find the screen gain in your setup.)

No offense Noah, but I don't think it does..."The HP will elevate blacks" states nothing of the whites, which are also elevated to the same degree as the black keeping contrast constant just like all other passive devices. A logic error of ommission does not necessarily change the truth value of a statement (though it can)...I think its a true statement, though incomplete.

Make sure that you don't compare screen materials at the same time. If you put them next to each other, one will certainly appear to have "gray" blacks because your brain is comparing the light level to the things around it.

Take for example that I'm using my projector now in a room with the lights on and the windows open. The text that I am typing looks as black as the velvet on my wall, however we know that this cannot be true if one were to measure it. The reason it looks black is because it is surrounded by much brighter light (the background of my web browser).

"Make sure that you don't compare screen materials at the same time."

This is the most important thing said here, as doing otherwise results in misleading comparisons

Purple? I hope you are kidding

I hope you mean the rock band

Steve, you continue to draw your info from the halftruth and deception well concerning the HP screen. Yes the HP screen can have a power of 2.8 but you continue to assert that 2.8 is the gain achieved in every setup. Will you please admit that this screen can also easily be setup to achieve a gain of 1.0or even less in many rooms. Not everyone tapes the projector to thier mine helmut or has a 46 inch ceiling height.

I didn't assert the gain was 2.8 in every setup. I merely used the manufacturers figure. Maybe you could write to Da-Lite and get them to change what they claim?

Sure you can set up the HP to have lower gain by ceiling mounting the projector. But why would you?

If you did, perchance, want a 1.0 gain High Power then the black level would, of course, be the same as a regular 1.0 gain screen.

blacks on my hp with hc6000 look great, not gray. They are a bit brighter than on the bare white wall but not not terribly so while looking very black when contrasted by brighter colors in the picture. The difference in blacks seems less than difference in whites and other bright colors.

I would not paint it Flat if you haven't done so. Flat is hard to clean and a slight egg shell is just fine and the reflections will be minimal.

scott

How'd it turn out??

Scott

Curious, what samples have you tried?

Yup. That is common. Remember that a screen with gain, especially a higher gain like the Hi Power, will reflect EVERYTHING....including the dark scenes. But, because it also increases the light scenes, the effect is usually not as noticable so most people don't worry about.

Comparing high gain samples with lower gain samples is highly misleading on blacks. In a real system with a high gain screen being used for the entire picture, your eye will adjust so that perceived black level looks black as it does on my system.

With sample of screen your eye is adjusting to average of all the samples so the blacks will appear gray because your eye can not adjust to the one small high gain sample. It will be fooled by relative light levels between screen samples.

In other words you have set up a situation which is essentially worthless in seeing how blacks look because, the most important factor, your eye adjusting to light levels is removed from the testing.

I have a bright projector (IN82) placed for maximum brightness for the High Power screen. I see blacks being black and no blacks being gray. The picture quality and colors are really good and a pleasure to watch.

Your test is essentially telling you to have a dim picture which could place your eye in a range far away from where you will see the highest quality picture.

Eventually you will be stuck with the gray screens. I have never seen a gray screen with a high quality image because the low light level screw up the perception of color for the eye. Run a test by going outside at night and see how good those colors are that look so good in bright day light. That distortion by your eyes is what you are trying to achieve.

In bright day light, look at something black. Is it gray? No it looks black. The intensity of the black lever in day light is far higher than anything you can produce with a projector and screen. You eye has adjusted in day light to make black look black.

Again, your reasoning is wrong and leading you towards a low quality picture in your theater because you have totally ignored what your eye does as it adapts to different light levels.