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After reading, reading, reading, I came to the conclusion that a BW screen was right for me. My projector is an Optoma HD65 with 1600 rated lumens. My HT is not well light controlled during the day as it has a sliding glass door with BO cloth curtains and a fluorescent light in the middle of the 12x17 room.

So I painted a BW screen and was happy. It was better than other greys I'd tried. Then I read some posts about how few DIY'ers had good reference points, and were not well suited to saying what was good and what was not. So I painted a bone stock Kilz2 test panel.

When I compared the Kilz2 to the BW screen. The differences were dramatic. The Kilz2 had clearly higher black levels with light present. However the white levels were also much higher. The BW screen clearly had better blacks, but the whites were beaten down so much that the image lost more than the darker blacks gave it.

It appears to me that the overall dynamic range of the pure white screen is higher than that of my BW screen. While my numbers are made up, they represent what it "seems like" to me and are after calibrating my projector (both screens had the same calibration numbers when using the THX optimizer).

Perceived dynamic range in a lighted room:
White = 100-255.
BW = 50-160.

Perceived dynamic range in a mostly dark room:
White: 20-255
BW = 5-200

Perceived dynamic range in a completely dark room:
White: 0-255
BW = 0-200

What am I missing? There HAS to be a reason that grey / grey relfective screens are so wildly popular with the WAY more knowledgeable folks than me.

-Jim
 

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When I compared the Kilz2 to the BW screen. The differences were dramatic. The Kilz2 had clearly higher black levels with light present. However the white levels were also much higher. The BW screen clearly had better blacks, but the whites were beaten down so much that the image lost more than the darker blacks gave it.
I don't think I could ever believe a statement like this without any pictures. A white screen has better blacks than a gray screen in ambient light conditions? I think this may be a typo!
 

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I don't think I could ever believe a statement like this without any pictures. A white screen has better blacks than a gray screen in ambient light conditions? I think this may be a typo!
I read "higher black levels" as meaning grayer blacks, not blacker blacks.:bigsmile:
 

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I read "higher black levels" as meaning grayer blacks, not blacker blacks.:bigsmile:
Ahhhh!

Well than you answered your own question then Jim!

What am I missing? There HAS to be a reason that grey / grey relfective screens are so wildly popular with the WAY more knowledgeable folks than me.
Because a lot of us like deep blacks over white whites. :T
 

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Hi James,

Welcome to the Shack!

First off, I think your basic statement that a white screen has more dynamic range (the range from the brightest part of an image to the darkest part of an image) is correct. It has to; Physics demands it. However; as with most things in life, it's not that simple. The dynamic range of our projectors is far from optimal and quite a bit less than a white screen has the potential to display (BTW, Kilz2 is not white, but a very light gray).

This will vary from PJ to PJ, but my own projector has a very gray black level, even when using a BW screen. Most of us still remember the dead blacks we used to get from the old CRT televisions. My projector (Viewsonic PJ503D) doesn't even come close to CRT black levels, but then neither does my Acer LCD computer monitor or Olevia LCD TV.

A gray screen slides our perceived contrast range down toward black. Do you lose white-level? Yes, but if not too much is lost our brain can fool our eyes into thinking everything is just fine. It's much the same as a good quality MP3; a lot of info is missing in what we hear, but our brain fills in the missing parts so it sounds just fine to the average listener. JPG image compression can be used as an analogy here as well; lots of data is missing from the image, but we don't notice it unless we look really close.

Now I will tell you why I like a gray screen over a white screen. I was one of the first beta testers of the original Black Widow mixes. My test screen consisted of five 1x4 foot panels side-by-side so I could compare the various BW mixes under projector illumination (a few were never released) against each other. Later I developed the Cream&Sugar screen mix for those that want or need a lighter screen than BW can give and I did the same type of side-by-side testing of C&S panels. At one point I had four C&S panels and one Kilz2 panel on my wall and started watching some movies on that composite screen (in case you don't know, C&S is a mix that is a bit darker than Kilz2, but due to a reflective ingredient it has the same white-level as Kilz2).

As I watched the movies I thought to myself "Hey, this looks pretty good. The blacks are almost as good as with BW, the colors aren't bad... hummm, maybe I don't want a dark gray screen after all." I changed DVD's and watched part of another movie and the image still looked good. I then popped in a movie I had used to test BW (The Fifth Element) and then things changed. Whites looked white, Blacks were still fairly black (about as black as my PJ gets), but something was missing from the image. It just didn't look right.

I took down the C&S and Kilz2 panels and put up BW panels, did a quick PJ calibration and then started watching The Fifth Element again. It was immediately apparent that what was missing from the C&S screens was what many call "pop". On the BW panels colors were richer, overall image contrast was better and the deeper black-level just gave the whole image an "edge" that the C&S and Kilz2 panels didn't have with my PJ and in my viewing environment.

In the end, what makes a good screen is subjective. Some will like a lighter or darker screen than others. Most people doing DIY screens won't bother testing multiple screen solutions, but they should. :)
 

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Discussion Starter #8
Thank you for the detailed response Harpmaker. I guess I should mix up some CS and see where that gets me. It sounds like I need to make some bigger test panels and try watching a movie rather than just putting up test patterns and test .jpgs. It's funny that you describe the BW as the one with the "pop". That is exactly the difference that I would have attributed to the Kilz2. My BW just seems so incredibly muted. Whites are not white but silvers, and it is noticeable. I want BW to be the right solution, it seems that so much work has gone into it that it MUST be better.... more testing will follow.

EAGLES: Yes, this was a diversion from testing the polycrylic. I primed the test panels with Kilz2 and decided to just throw that up before I put on the poly mix. I was so impressed with the "very light grey" of the Kilz2 that I started to question why I wanted a grey screen to begin with.

-Jim
 

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James another welcome to the Shack!

Your statements are true but hopefully one of the things you also read along the way was it really is impossible to compare a white screen to a gray screen and come away with anything other than the whites are whiter on the lighter screen, and blacks are deeper and darker on the gray screen. This even holds true with commercial screens.

If you are properly calibrated for the gray screen once you remove that white reference screen your whites on the darker screen will now appear as white again.

Some people prefer the deeper blacks while others want the whitest whites possible. In that sense it is a personal preference. There is however a reason for gray screens and that is mainly with ambient light or lighting issues. Also lower CR projectors benefit from the perceived increase in contrast. Notice I did not say actual increase because a screen can not create something above what the projector is putting out, but we can trick ourselves into percieving a better contrast ratio.

One of the main reasons I always tell people to do a baseline calibration on a white reference screen is so they can see how the projector looks at 'factory specs'. Without doing this it is impossible to decide if you like one screen over another.

Nobody will take offense if you say you like a white screen better than BW, that certainly is your preference if that's what you decide. Keep in mind that they are two very different types of screens and used for different reasons. Another way to look at it is like this... Think of how much it would cost to buy something like say a FireHawk and decide you don't like it and end up having to buy a white screen. That is one of the unsung benefits of DIY!

No matter what type of screen you end up with make sure you calibrate the projector to that screen, it really does make a major difference.
 

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Thank you for the detailed response Harpmaker. I guess I should mix up some CS and see where that gets me. It sounds like I need to make some bigger test panels and try watching a movie rather than just putting up test patterns and test .jpgs. It's funny that you describe the BW as the one with the "pop". That is exactly the difference that I would have attributed to the Kilz2. My BW just seems so incredibly muted. Whites are not white but silvers, and it is noticeable. I want BW to be the right solution, it seems that so much work has gone into it that it MUST be better.... more testing will follow.

-Jim
May I ask what base paint you used to make your BW? Did you use Auto Air Aluminum (fine)?

Also, do you have much ambient light in the room when watching your PJ? Do you have light or dark walls, ceiling and floor? My viewing environment is white walls, shiny white ceiling and natural cement floor, so I have a fair about of ambient light even with all lights off (there are no windows).

One should never compare a very light screen to a very dark screen side-by-side. The light screen will always have whiter whites, but lighter blacks, and the dark screen will always have blacker blacks, but dimmer whites. If you read the C&S thread ( http://www.hometheatershack.com/forums/projector-screens-diy-screens/10528-cream-sugar-n9-reflective-screen-mix.html ) you will notice that I have two BW panels beside the C&S and Kilz2 panels. I really shouldn't have done that for the reasons stated above. I also over-shared some of the technical data, but I wanted to show how the mix was developed. If you were liking the Kilz2 better than the BW perhaps C&S would work better for you.

Something doesn't sound right; you should be using different PJ settings, if only slightly, for Kilz2 and BW screens. There is a whale of a difference between those screens. I don't know what's going on.:dontknow:

BW is a very good screen solution, but it isn't right for everyone in every situation. Yes, a lot of work and testing when into Black Widow (and it is still on-going), but that doesn't mean it's THE solution for every home theater (although it's getting closer ;)).

I, personally, see more difference between mixes when I use test patterns. I now test with a 100% White Field image from the Digital Video Essentials DVD, a horizontal color bar image from the same DVD and a contrast bar (or gray bar) image that Tiddler made up. When watching movies, I notice the greatest differences between mixes in very light scenes and very dark scenes. I have even watched a few scenes where I couldn't tell the difference between panels at all!
 

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Discussion Starter #12
Thanks again for the replies. I used Valspar Ultra Premium Flat with the AAA. I just read a thread saying there was significant improvement with going to the Flat Enamel over the Flat.... my Loews only had flat in stock and I got that instead.

Now I'm going to have to go get some Flat Enamel and some more AAA.....

The rest of my setup is: I have dark crimson walls, with bright ceiling and floors. I'm planning on painting the ceiling grey soon and getting darker carpet. I want to use the system for party games on the Wii as well as for HT. That's why I've been convinced for so long that a grey screen was right for me.

As to the calibration difference. I went back and tried again. I ended up having the contrast turned up one notch and brightness up 2 notches for the grey screen. Not dramatic differences, but worth doing. I haven't had time to be critical of the picture yet after the adjustment.

BTW: I went to Magnolia today and had a look at a real live firehawk. It's hard to compare but I'd say the BW screen at least held it's own vs. the firehawk, and I'm pretty sure I like the BW better. After my jaw dropped when I was told the price. I quickly said thank you and thanked my lucky stars for BW.

Is the N8.5 BW ready yet? That is sounding quite nice right now.

-Jim
 

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A lot of DIY solutions are pretty good compared to expensive screens like the firehawk. I go home feeling happy and proud with my DIY screen. Actually my screen is only part DIY, I use Black Flame which is a "commercial" version of silver fire, I made the frame myself though. :bigsmile:
 

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Sorry Jim, I thought I had replied to your last post, but see I haven't.

Yes, the Valspar Ultra Premium Enamel (flat) provides a much better base for BW than the regular Valspar Ultra Premium flat latex. While almost any kind of water-based paint can be used to make the original BW mix (as long as it's tinted to match PPG-Bermuda Beige); some kinds work better than others.

Yep, DIY screens give the commercial screens a run for their money, and many times better them while costing MUCH less. And it's sooo cool seeing the look on peoples faces as their jaw drops and they say "YOU made that!?".:bigsmile:

The lighter BW mixes are being beta tested, more news when we get feed-back from the testers.
 

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And it's sooo cool seeing the look on peoples faces as their jaw drops and they say "YOU made that!?".:bigsmile:
+1! :T

I have a carefully painted screen painted directly on the wall. Friends are bowled over by the PQ. They are awed by the 110" size and can't believe the resolution, and I'm using a 720p projector.

I was at the local big box the other day. I looked at the BIG LCD screens. I guess it's a matter of preference, but I like the movie like quality from FP.

Doug
 

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+1! :T

I have a carefully painted screen painted directly on the wall. Friends are bowled over by the PQ. They are awed by the 110" size and can't believe the resolution, and I'm using a 720p projector.

I was at the local big box the other day. I looked at the BIG LCD screens. I guess it's a matter of preference, but I like the movie like quality from FP.

Doug
Doug I'm with you... I like the look of a projector for movies because to me they look more film like. Yes HDTV's have that back lit bright vibrant image, but often it is borderline over saturated and rarely looks like real life... but it does look good I'm not saying that. They just look 'different'
 
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