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Discussion Starter #1
Hi! First post here after alot of reading. I would like some advice regarding my diy screen painting.

I am in the middle of my first attempt at building a screen for my first projector (Infocus X9, rated at 1800 video optimized lumens).

Since I have a pretty bright projector, and i wasnt really happy with the black levels with what im using now (white wall), I decided to try and build a Black Widow clone. Looking at other peoples screenshots, and comparison with other gray screens, it just seems to be a very good choice.

What i did was build a frame out of wood and then stretched artist canvas over it. So far so good.

Then I got the AAA paint, and what i have understood to be the correct color for europe to mix it with: s0907-y70r.

I wasnt sure what shine to get it in, so i got it in level 5 gloss (flat or matte is like 3 over here, and regular wall paint about 7).

I then painted a small testpanel with AAA s0907 1:4 concentration to see what it would look like. I made a bach of 1dl of AAA, and 4dl of s0907, that is correct right? Now, here comes the problem:

The whites are not even close to white. They look almost as gray as the testpanel does really. This is especially noticable in bright scenes with lots of white content, and even much so when i connect my xbox and try to play mirrors edge (which is a very bright game, with lots of white, bright scenes) Granted I am comparing to the white screen (I know this might confuse the senses a bit), but is it really normal that whites looks like noticable gray when using gray screens?
Comparing to a gray piece of cardboard I have that is about the same darkness, the whites look almost the same as the BW paint. Seems the aluminum isnt helping at all in my mix to me. From most screenshots ive seen of the BW screen the whites look much better than it does on my testpanel.

Can I make the BW mix lighter atleast to make it less apparent that the whites are actually dark gray? Like 4:1:1 or 4:1:1.5 using white paint in the mix to lighten it?

Or am i expecting too much from this mixture?

Btw, my image size on the wall right now is 104" diagonally, and according to the projection calculator over at projection central, that should be around 52fL on my white wall. Plenty of light output, right? (I normally turn down the brightness during nighttime viewing, and run the projector in eco mode)

Will the upcoming lighter BW mixes also be based on the same colors+ added ingredients, or completely new ingredients? Im trying to decide if i should keep most of my expensive AAA paint until I can make a lighter version of the screen if its not advised to just add white paint to it.

Thing is, I am using the projector in my living room, have white walls and ceiling. So the added benefit of ambient light rejection with a darker screen would really be at good use here if i could only get it to work for me.

Any advice on my situation what to do would be greatly appreciated.

Thanks!
/Jonas Hagberth
 

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firstly welcome to the shack jonkan.

you are right. the whites are going to look darker than a white screen.
but the blacks will also be deeper aswell.

the whites will beat an equivalent N8 grey panel. your wall is probably in the region of N9.5.

to maximize the reflectivity i would advise you to place the projector under the ceiling not on a table top.

i dont think you will have a problem with the BW after you have calibrated to it.

you will be surprised how well the eyes adjust once you are not comparing. the overall picture is improved.

BW can be lightened by adding one part white so the ratio would be 4:1:1.

the lighter BW mixes have not been completely finalised yet, the final product may utilize the AAA you have already. but i cant say when it will be ready.
at the moment the base needs to be spectroed by mech and harpmaker before final testing is completed.

the developers forum will give you an insight into how testing is progressing.
 

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Jonas,

Welcome to the Shack! :T

I'm hoping custy can double check your paint and it's sheen value. We use a matte base for BW here in the US. Flat has worked for me in the past but not for others.

Now as to whites and blacks, the whites should be equal to a N8.5 or so and the blacks should be equal to a N7.5. There's a thread here that may help some. Whites will never look white on a gray screen when comparing them to anything white. You must take into consideration the whole image. Do the whites look gray on these images?





They do not. But they are actually gray and my eye's perceive them to be white. This reminds me of my original opinion of Wilsonart Fashion Grey. I had been using Parkland Plastics Polywall, which is probably on the same scale as Cream and Sugar. I put the dark gray FG up and hated it. The whites were off and it seemed to hot spot badly. Then I re-calibrated and everything looked 100 times better.

We've got some very good threads here on comparing grays to whites. Here's a gray and white laminate comparison. And here's the polywall and Fashion Grey comparisons.

Adding white paint to the mix has not resulted in a lighter mix. There was a lot of investigation in to this by wbassett and myself here.

That sure is a light cannon. I get 49fL for a Black Widow screen that's 104". How does it look on the white wall? The lighter Black Widow mixes are still being worked on... slowly. We're unsure as to what it will require at the moment. Maybe in a month or two we might know more. Normally I'd suggest Cream and Sugar. But I don't think you can get the Craft Smart product in Sweden. And there isn't any suitable substitute for it yet.

My advice? You have the Black Widow ingredients. Paint the screen, recalibrate and stop comparing it to a white wall. I think you'll end up liking it. :T
 

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Thing is, I am using the projector in my living room, have white walls and ceiling. So the added benefit of ambient light rejection with a darker screen would really be at good use here if i could only get it to work for me.
I just remembered something regarding this! There's a commercial flight simulator in Australia using BW as their screens for a reason very similar to this. They were having trouble with the reflection from the adjacent screens. Not anymore though! :bigsmile:
 

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BW can be lightened by adding one part white so the ratio would be 4:1:1.

.
i should have said it can be lightened slightly only:innocent:

i an unsure of the number system used for sheen in sweden as we in the uk donot use it.
i am using matt which has a higher sheen level than flat matt.

there is no internationalised standard so i can't say if level 5 is appropriate.
 

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Discussion Starter #6
Thanks for welcoming me! I will read all of your suggestions and report back.

I have tried both the 4:1 mix, and the lighter 4:1:1 mix, and so far I like the 4:1:1 mix more. It doesnt kill the whites as much, but still remains alot better in the blacks than the white wall.

About the sheen. 2-3 is about the least sheen you can get over here i think. 7 is like a normal interior wall sheen (a bit shiny, but not so much), and 5 is a bit matte, and not so much reflective, but you can still clean it with a wash cloth without ruining the surface (which you cannot with sheen nr 3 for instance, without ruining it).

Looking at the comparisons with the white and gray screens, i must say that the difference in whites is much smaller between the screenshots, than it is between my white wall and my BW testpanel. My whites looks alot less white by comparison to the white wall. Im thinking it might be some problem with my mix, or maybe the way ive painted it?

If the 4:1:1 mix is deemed to be okay, ill probably try that first and see how it works out. What do you think?

Btw, thanks alot for helping me out!
/Jonas
 

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I'm a little late to the party, but I'll welcome you as well Jonas. :)

I think you are getting trapped by a situation that many have fallen into, namely, comparing a white screen directly against a gray screen. When that is done the white screen will always have whiter whites and the gray screen will always have blacker blacks.

The way a gray screen works (all gray screens, not just BW) is that when our eyes have no other reference and they see an image that we know contains something white, like snow, we see it as white and our brain interprets it as white; even though it's really gray. It is a form of optical illusion, but it works in our favor as long as the screen isn't too dark for the projector being used. Your PJ has more than enough lumens to successfully use a BW screen.

I highly recommend watching a movie on the BW screen with no part of the image hitting any white surface, just the BW screen. If you have a video calibration DVD, use it to calibrate your PJ to the gray screen. I think you will be amazed at how white the whites then look. Yes, they will still really be gray, but they will look white as long as there is nothing brighter than the BW being projected on.

BW is a gray screen; what makes it better than a regular gray paint is that the aluminum flakes in it cause it to reflect the brighter colors as if a regular gray paint of a lighter shade is being used while retaining the blacks of the dark gray screen that BW is.
 

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Discussion Starter #8 (Edited)
Thanks! I guess ill try and paint it then, and hope ill like it.

One more question: If i want to run the projector in eco mode to save the lamp, which is about a 20% drop in brightness, will that still be enough for the BW? Or should i go for the 4:1:1 mix first?

The X9 only has one user mode, which seems to me, to be as bright as the "movie" mode, and that has been reported to be around 1003 lumens at 6574K. So if i dont want to recalibrate the other, brighter non usermodes that doesnt save the settings every time i start upp the projector, ill have to use it.

So in my estimation, around 800 lumens. Is that enough for a BW at 108" diagonal screen?

Or should i use the brighter modes and just live with the pain of entering the calibrated settings everytime i start up?
The Game mode looks almost as good as the movie mode colorwise, but is about 1500 lumens in ecomode. Alot brighter it seems. I Wish you could save all the settings, I dont understand why infocus didnt include this in the firmware.

Since this is my first projector, I really have no frame of reference on what is normal, or reasonable to expect, so thats why im so full of questions. I hope you can bear with me!

/Jonas
 

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Jonas,

The beauty of paint is that you can always paint it again! As for the lumens, I figured my old bulb (just replaced with new) was hitting my 100" BW screen with ~325 lumens. I would think 800 would be fine. :T

mech
 

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Jonas - can i ask where your projector is placed?

to maximize the angular reflective potential of Black Widow it is advisable to place the projector in the ceiling position.

the table top position is advised for glass beaded retroreflective screens.
 

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Discussion Starter #12
Sadly, I have to keep the projector on a table. Girlfriend wont let me ceiling mount it, thinks its ugly and unnecessary. I should be happy I was able to make room for the screen actually.... ;)

How big of a difference will it make?

/Jonas
 

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from testing of lighter black widow screens, i can say there is still an increase in reflectivity for your setup but not as much as in the ceiling position.
if your girlfriend will not allow the ceiling posion for the projector then i would advise you try and place the screen in the lowest position that is acceptable to you.

i'm sure the other guys will have some opinions on this aswell...
 

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Discussion Starter #14
Just wanted to update you guys on my screen build. As of now i have painted my canvas screen with 3 layers of 4:1 Black widow mix.

I accidently made an ugly black mark on my screen surface when building the border, so i will have to be a fourth layer aswell...good thing i bought the big AAA bottle. Too bad i wont have any left for more experimenting after this though.

Anyway. I cannot see any aluminium at all on my finished painted surface, even though im using a bright lamp pointing directly at it, and im looking from a very close distance too.

Is this normal, or is my paint too "good" at swallowing the aluminium?

I havent mounted it on the wall yet, but ive tried projecting on it as is and atleast it looks alot better than my white wall. Im just not sure if the whites are any better than expected from a normal grey screen of the same darkness. Big white fields look, well a bit grey. But in normal images, the whites looks white by comparison to the better blacks.

Thanks for any advice!
/Jonas
 

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Hi Jonas,

The 4:1 BW mix with AAA is not a "sparkly" screen by any means, but you should be able to see some of the small aluminum flakes if you are within a hands width away from it.

Since we don't have access to the exact brand of paint you are using, we can't really tell what you are seeing. If you could make up a small sample (a business card sized piece of white cardboard painted with your mix) and mail it to either mech or I (mech has the better equipment) we could then examine it and give you better feed-back. If you're willing to send us a sample, just PM us for an address.

While your paint may be too "good" (meaning good at hiding other colors), I really do think that the aluminum will still give you a better screen than a regular paint the same shade of gray.

Just as a matter of curiosity, can you get Golden or Liquitex brand artist paints where you are? They are both international companies, but I don't know their availability in Sweden.
 

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Discussion Starter #16
I finished my screen today, will try to post some pics soon. I just have to hang it on the wall, and im all done. Im no carpenter, but in the end it still turned out pretty ok i think.

I have looked, but i still cannot see any aluminium flakes at all on my screen. Strange thing is that i can clearly see the aluminium on my test panels made of cardboard with the same paintmix.

So it would probably not be of much use if i sent you a cardboard sample since I have painted my screen on cotton artist canvas that was primed for acrylic paints. I dont have any spare canvas to send to you (I dont have any more AAA paint either, and its very expensive over here, so im really hoping this mix will work for me)

I have tried projecting some random images to it, and first impression is that it looks great anyway, so im not really complaining or anything. Looks alot better than my wall for sure!

Ill snap some screenshots as soon as i can get the screen up, and maybe you can tell if it looks normal or not.

Harpmaker: I have never heard about those paint brands over here. We mostly have nordic brands i think, and not so many that might be more readily available in the rest of europe.

Thanks for doing such great DIY research btw. Internet really is a wonderful place, where all this knowledge can be found and shared.
/Jonas
 

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Looking forward to your screen photos Jonas.

And again, I think the aluminum flakes will still be working even if you can't see them on the surface. Let me tell you about something that happened while experimenting with the lighter versions of BW (which are in a holding pattern for now). When I first started making my test panels I saw VERY little aluminum in the dried paint! I tested that panel anyway and found that it did indeed work (it was brighter under projection than regular gray paint the same shade). Now the interesting part - when I took down the panel I found that where I had touched it with my nitrile-gloved hand there were plenty of aluminum flakes winking back at me! I then made up another test panel and when it was dry I rubbed it all over with a gloved hand which made the whole panel sparkly. Now the REALLY interesting part - BOTH the sparkly and the non-sparkly panels worked the same, there was no visible difference at regular viewing distance (about 10 feet)!

I would have liked it if you could see a few aluminum flakes in your screen, but I know they are in the paint and at least some of them will be active. :T

The Golden and Liquitex brand paints are ARTIST paints and would be sold by stores that sell to people making their own oil and acrylic paintings like portraits, landscapes, still-lifes etc..
 

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jonas - i missed the point that you were using canvas as your screen previously.

a few people used pre-primed canvas in the UK. one of the problems they had was that alot of paint was being absorbed in the voids.
they had to use alot more paint compared to painting on solid substrate.

in hindsight it may have been an idea to still use a white primer paint even though it was pre-primed, so as to use less of the BW mix filling the voids.

did you roller or spray the screen?

telling us about your experiences with painting canvas will help us and others who are contemplating using flexible substrates:T
 

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Discussion Starter #19
I did roller it, using a smaller roller that was recommended to me by the paint seller for leaving less texture marks. You are right about it needing a bit more paint due to the canvas texture i think. I needed about 3dl of AAA for four layers of paint. I might have enough mix left for one more layer i think.

The Artist canvas has some texture, so id image it not being optimal for projections. But its still alot smoother than what my wall is, so i think its fine (atleast for me).

The only trouble i had with artist canvas is really that its not a "dead" material. I had some problems with small wrinkles which i tried to get rid of using some water on the back of the canvas after i stretched it. These would not go away no matter how hard i stretched the canvas on the frame (I used a stretcher plier so its pretty tight).

After I applied water to the back the canvas shrunk a bit in that area and a visible mark could be seen even worse than it was before. It worked too good basically at shrinking the canvas. What I ended up doing was actually spraying the whole back with water, and then went over it gently with a hairdryer. That seemed to even out almost all problems i had. In the end, I cannot see any unevenness from the front of the screen. If you look from the side you can still see some very small lines from where the canvas was primed by the canvasfactory (they were not as thourough painting it as i was).

The canvas being uneven might have had something to do that i bought the cheapest cotton canvas i could find also.

The end result looks fine to me, but alot more work i imagine than just using a flat, stiff substrate. The weight is pretty low, which is nice.

Harpmaker: I could indeed find the Liquitex colors here in sweden at an artstore. Do you have any nice paintmixes in mind for them? The Golden Acrylic ones, ive yet to find.

Good to hear about the aluminium working without visibility too. Gives me hope that my screen might actually be one of the good ones. I found the same thing as harpmaker when i tried to get rid of a small hair that had gotten onto one of the layers. I gently scrubbed it with a rag, and then suddenly i could see alot of sparklies in that area. So its definately there, just under the surface. Still cant understand though why they are more visible on cardboard than my screen.

Hopefully i will have time to get the screen up on the wall today.
/Jonas
 

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Harpmaker: I could indeed find the Liquitex colors here in sweden at an artstore. Do you have any nice paintmixes in mind for them? The Golden Acrylic ones, ive yet to find.
/Jonas
We sure do! They are still in testing, but things are looking good so far.

We are finding that some base paints are better at making BW than others, and when you add international brands into the situation the variables increase even further. I want to be clear that all bases tested in making BW have worked, it's just that some worked better than others.

Our thinking is that if we can find a base paint that is available in most countries, it would ensure that everyone can get the same results we get in our testing. The only paints we have found that are truly the same world-wide are artist paints.

In the U.S. both Liquitex and Golden artist paints are heavily discounted so their cost is not much, if any, higher than top-quality house paint. We are hoping that the same discounts can be found in other countries as well; but even if such discounts can't be found, the price of a good DIY screen will still be much less expensive than a commercial screen of similar quality.
 
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