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I'm new to this Home theater malarkey... Been building my setup for two or three weeks now, I'm now at the stage of making my screen, the way i see it i could take the easy way out and "just" buy the screen, but i want to tell every one its all my own work ... so to you more experienced.... please forgive me if i sound a little Errr thick !! I'm not really :innocent: I'd like to build my screen from MDF board, now before i paint it do i need to prime it and if so with what, Next I'm confused about the screen top coat..... Do i use the Dulux or B.W also I've been any advice please ! also I've been following some talk about mixing 4 parts s0907-Y70R to i part CTX-4101 Auto Air Aluminum, is this BW ?? :doh::dontknow::dontknow: ...
 

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Re: DULUX Exterior Paint vs. Black Widow

Hi Ivor, welcome to the forum! :wave:

Front projection screens can be a confusing topic since there is a fairly large amount of misinformation on the 'net about it. In a dedicated theater (black or very dark colored walls, floor and ceiling) with no room lights on during viewing and using a projector that has very good black levels to begin with, the perfect screen would be a bright flat white. This would produce the brightest image with the widest viewing cone (people viewing from seats close to a side-wall would see the same image brightness as those seated in the middle of the room). The problem is that very few people have dedicated theaters, and very few projectors produce black levels that don't need at least some help. The answer to both problems is using a gray screen.

Gray screens absorb some of the light that hits them, both from the room (ambient light) and the projector. The net effect is that perceived image contrast is increased (no screen can produce more contrast than the projector is capable of) which helps make blacker blacks and more saturated colors. Through a type of optical illusion, the eyes are fooled into seeing white images on a gray screen as being truly white unless the image to too dim; with todays bright PJ's this isn't much of a problem unless the screen is extremely large.

For us to suggest a screen for your HT we will need to know:
1. The projector being used.
2. The size screen you intend to make.
3. How far away from the screen the projector will be mounted.
4. The color (bright, medium or dark) of the walls and ceiling in the HT.

I would suggest that you prime your MDF before applying the actual screen mix. Priming does three things, it seals the substrate so it won't absorb the screen mix, it gives a bright uniform color to the substrate and it gives the screen mix a more "sticky" surface to adhear to. Since most untinted primers are white, we also advise that the primed substrate be used as a white screen to calibrate the projector, and to give the user an idea of how a white screen will perform in their HT. Watch some video on this screen and note what you like and don't like about the image. If you want deeper blacks (or more contrast in general) than a white screen gives you then paint the screen with a gray mix.

What our reflective gray screen mixes do, compared with regular gray paint, is provide a darker gray surface to absorb ambient light while providing a seemingly lighter gray when under projection due to the directionality of the PJ beam and the reflectance of the mix. All our mixes are also very color-neutral which means that the screen is reflecting the same colors that the projector is shooting.

I'm not quite sure what you are asking in the last part of your post. Our Black Widow™ screen mix is made up of a single color base paint to which is added Auto Air Aluminium-Fine (AAA-F for short). The base paint is tinted at the store to match a color called PPG-Bermuda Beige (PPG is a paint brand). The corresponding color in the NCS color system used in the U.K. is s0907-Y70R. The color is a pinkish beige which is required to off-set the bluish tint caused by adding the AAA-F. The result is a very neutral gray.

4 parts s0907-Y70R to 1 part AAA-F is the formula for BWuk. Many use Dulux paint to make BWuk, but other paint brands will work as well as long as they can be matched to the s0907-Y70R color.
 

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Re: DULUX Exterior Paint vs. Black Widow

For us to suggest a screen for your HT we will need to know:
1. The projector being used.
2. The size screen you intend to make.
3. How far away from the screen the projector will be mounted.
4. The color (bright, medium or dark) of the walls and ceiling in the HT.
I would love to hear a suggestion. I've been reading and researching and reading some more now for a couple of weeks. I've thought about paint, OTS screens and DIY screens. I've got an Optoma HD66. I'd like to sure a 110" diag screen. Per the Optoma website, my throw will be about 12'7". Currently the room is painted a light peach color (see attached). The ceiling is white.
 

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Hi BuckeyeGuy, Welcome to the forum! :wave:

At first blush, the HD66 looks to be a very bright PJ (which it is) that could use a simple OTS gray screen (which it could) with factory settings, BUT things get a bit more complicated when one gets into the details of this PJ.

According to ProjectorCentral (review here), this PJ really should be calibrated to get dark blacks and accurate colors. Doing this will decrease image brightness significantly, but also increase image quality significantly as well. The good news is that the PJ is still bright enough to use a gray screen. :T For your screen size, I would recommend our Black Widow™ mix which is a N7.5 in gray level (0 is pure black and 10 is pure white).

If you use ProjectorCentral's Calculator (here) you will see that it says you are getting 34 fL. at 110" with a 16:9 AR. This brightness drops to just over 16 fL. after the PJ is calibrated and low-lamp mode is used.

Another thing that will affect your screen size a bit is what Aspect Ratio you will make your screen. In your drawing you have selected to use 16:10, which is the native AR of the 1280x800 DLP chip, but this AR is only used when the video source is a computer, if you never intend on using a computer as a video source you are probably safe to make your screen 16:9 which is standard for HD.
 

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Hi BuckeyeGuy, Welcome to the forum! :wave:

At first blush, the HD66 looks to be a very bright PJ (which it is) that could use a simple OTS gray screen (which it could) with factory settings, BUT things get a bit more complicated when one gets into the details of this PJ.

According to ProjectorCentral this PJ really should be calibrated to get dark blacks and accurate colors. Doing this will decrease image brightness significantly, but also increase image quality significantly as well. The good news is that the PJ is still bright enough to use a gray screen. :T For your screen size, I would recommend our Black Widow™ mix which is a N7.5 in gray level (0 is pure black and 10 is pure white).

If you use ProjectorCentral's Calculator you will see that it says you are getting 34 fL. at 110" with a 16:9 AR. This brightness drops to just over 16 fL. after the PJ is calibrated and low-lamp mode is used.

Another thing that will affect your screen size a bit is what Aspect Ratio you will make your screen. In your drawing you have selected to use 16:10, which is the native AR of the 1280x800 DLP chip, but this AR is only used when the video source is a computer, if you never intend on using a computer as a video source you are probably safe to make your screen 16:9 which is standard for HD.
Thanks for the info. I read the review but admit that I've looked at so many that I had forgotten the info regarding fL. Not to mention I've had to do a whole lot of reading to figure out what fL is and how to calculate it. It's been fun though. Knowledge of any kind is good. As for my AR, let me ask this. I don't plan to use 16:10 a whole lot, but that's me talking today and that might change. I sure would hate to set up a screen (16:9) and figure out I wish I would have done one for the native AR. That being said, when I paint the screen will I see the unused portion of the screen? Does the projector project light there? I guess I'll have to mull over what to do based on your answer to the above question. One more thing....I can't find the link to see pricing and buy the paint.
 

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As you probably know by now, fL. is short for Foot Lamberts which is also known as lumens per square foot and denotes the brightness of a reflective screen. To manually calculate fL. simply divide lumens for the PJ mode in use by the square feet of screen surface (width in inches multiplied by length in inches and then divided by 144).

I don't know if the HD66 has any form of self-masking or not, but if it doesn't I would expect it would have small horizontal "black" lines on the top and bottom of the screen when showing 16:9 material on a 16:10 screen. I said "black" because while these areas should technically be black many times they are really a dark gray. If you already have the PJ you could find this out for yourself by projecting on a wall and comparing the two modes. Using a gray screen would help darken these "black" lines, perhaps even to a true black.

Black Widow™ is a DIY screen paint mix. Details can be found in the following threads:
Black Widow PFG - the Presentation - Black Widow

Black Widow PFG - the Discussion - Black Widow

It is a screen mix made from only two different paints mixed together. The base paint can be purchased from Lowe's (Valspar brand paint) and Home Depot (Behr brand paint), or any other brand of flat latex paint that can be tinted to match PPG-Bermuda Beige (which is the name of the paint color). The reflective additive is Auto Air Aluminum-Fine #4101. The AAA-F may have to be ordered by mail or on-line if a source can't be found locally. We prefer to use the Valspar and Behr flat latex enamels because they have a touch more gloss than a true flat latex, which makes the screen easier to clean and provides just a hint of added gain.

There is no measuring required to make BW™, just pour a quart of the base into a mixing pail and pour in two 4 oz. bottles of AAA-F and stir. The result is 40 oz. of screen mix, which is more than enough for your 110" screen. We recommend using a white primer as an undercoat and applying at least two coats of BW™ if rolling. If spraying, the number of coats will vary depending on the spray gun used.

A Black Widow™ screen has the same appearance and gain as a commercial Stewart GrayHawk screen while costing thousands of dollars less. Yes, it's true. We have the hard data to prove it. In fact our BW™ mix is even more color-neutral than the GrayHawk.
 

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Harpmaker wrote:
Is Kilz Oderless Pigmented Ultra Primer still the recommended primer?
There is no reason you couldn't use the above primer, but it is oil-based and would have quite a smell to it while painting and drying. We usually use a water-based primer for less smell and easier clean-up. I have used the water-based primers Kilz2 and Kilz Premium as well as several from the Zinsser brand and even a cheap Glidden primer designed for dry-wall. My personal favorite is the Kilz Premium (least amount of smell), but it really makes little, if any, difference in the end screen.

If you are going to paint the screen directly on the wall (easiest and cheapest method), be sure the wall has an even texture and no little indentations or "pock marks" which might allow the BW™ to pool when wet. Please don't misunderstand, you don't need a "baby smooth" surface like other forums are telling users, just one with an even texture and no areas that might catch and hold the wet paint differently than other areas. The wall doesn't even need to be perfectly flat, just flat enough so the entire image is in focus.
 

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...I've been following some talk about mixing 4 parts s0907-Y70R to i part CTX-4101 Auto Air Aluminum, is this BW ?? ...
I have rechecked the NCS code for US Bermuda Beige RGB 233,211,199 (#E9D3C7). It is not NCS s0907-Y70R with a RGB of 234,221,216 (#EADDD8) :eek: commonly used outside the US for BW clones.

The closest match to US Bermuda Beige is NCS S1013-Y66R with a RGB value of 232,211,199 (#E8D3C7) :bigsmile:

Best regards!
Darker_plz
 

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I have rechecked the NCS code for US Bermuda Beige RGB 233,211,199 (#E9D3C7). It is not NCS s0907-Y70R with a RGB of 234,221,216 (#EADDD8) :eek: commonly used outside the US for BW clones.

The closest match to US Bermuda Beige is NCS S1013-Y66R with a RGB value of 232,211,199 (#E8D3C7) :bigsmile:

Best regards!
Darker_plz
While I realize that NCS s0907-Y70R doesn't match the RGB numbers for Bermuda Biege on paper (NCS' paper), it matched just fine with my spectro. And while I've only measured the one sample of NCS s0907-Y70R, I've measured a few UKBW samples and all were neutral. So it does work just fine. :T
 

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While I realize that NCS s0907-Y70R doesn't match the RGB numbers for Bermuda Biege on paper (NCS' paper), it matched just fine with my spectro. And while I've only measured the one sample of NCS s0907-Y70R, I've measured a few UKBW samples and all were neutral. So it does work just fine. :T
I've Followed the instructions on the BWUK paint to the letter, being a newby at this i wasn't really knowing what to expect :dontknow: anyways i used MDF board, used a good primer then set about the top coat. i found it really easy obtaining the two parts to mix. B&Q ware very helpful this is where i got the s0907-Y70R ( Dulux mix ) the CTX-4101 Aluminum i got from the web.
i used a 4/1 mix, gave the MDF five rolled coats being a hot day i gave it one hour between coats. the screen ended up looking very, very good. wasn't sure what i was expecting but since I'd mixed Aluminum in to it i was thinking i would see Silver (specs) ..:ponder: not knowing if i would or not .... I didn't !!
now the screen it finished and on the wall, and must admit i have a low end projector (Sanyo SE20A being my first ) i wasn't very impressed with the picture, it seemed "dull" advice from the forum suggested i would find "Digital Video Essentials" useful which i bought "new" with filters.
DVE did do a good job and improved the picture by 40% ..... I'm now a very proud owner of my very own "cinema" ...... but the wife is now moaning as I'm now on the outlook to upgrade the pj .... Thanks to the chaps for their knowledge and advice :clap: :clap:
 

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Glad you are enjoying your HT Ivor. :T

There should be visible aluminum flakes in your BW™, but only if you get within inches of the screen. From anything approaching normal viewing distances when using a projector a BW™ screen should simply appear a solid neutral gray, but the very small aluminum particles in the mix are working to reflect more light back to you than a simple paint of the same shade.

As you have found, properly calibrating your PJ to your screen can have a tremendous impact on image quality. All of the problems that I remember people reporting with Black Widow™ screens have been resolved by either letting the screen dry overnight (it's too glossy while it's still wet) before judging image appearance or by calibrating the PJ.
 

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Glad you are enjoying your HT Ivor. :T

There should be visible aluminum flakes in your BW™, but only if you get within inches of the screen. From anything approaching normal viewing distances when using a projector a BW™ screen should simply appear a solid neutral gray, but the very small aluminum particles in the mix are working to reflect more light back to you than a simple paint of the same shade.

As you have found, properly calibrating your PJ to your screen can have a tremendous impact on image quality. All of the problems that I remember people reporting with Black Widow™ screens have been resolved by either letting the screen dry overnight (it's too glossy while it's still wet) before judging image appearance or by calibrating the PJ.
Just given the screen a good look.... i can't say for certain i have any silver flakes but that may just be the light in the room when i looked. but can confirm it is a really good neutral gray.
i give it another look when the room light is better and maybe post some pictures for you chaps to give your opinion......
 
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