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My guess would be that if you could see individual flakes of silver in the dried sample, that paint would be too coarse to use in a screen mix. The flakes act as little mirrors and if they are too big they actually reflect too much light and are too bright.

Never be afraid to ask questions, that is how we learn. :T
We use silver for two reasons; to darken a mix to improve perceived screen contrast and to provide a reflective element to the paint. The reflective nature of the silver paint is part of the plan. The small silver "mirrors" are dispersed throughout the white paint, this darkens the paint a bit (actually a lot when using aluminum flakes), but each flake (or mirror) dries in a random position which helps give a random reflection angle to the light that hits it. Reflection from gloss is only a surface phenomenon while even the silver flakes that are below the surface are still reflecting light when using metallic particles since very few paints are truly opaque.

It is fairly easy to create a neutral gray paint without using silver paint. We want the reflective "mirror-like" nature of the particles, it provides a boost in white-level of the image without hotspotting. Due to the randomness of the particles in the mix we do not get a "dark mirror", but millions of little bright mirrors that help boost image brightness without hotspotting. It is a very interesting effect. :bigsmile:
 

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Well, all I can say, it seems to work :yay2:
:jump:

My sample board has cured 18 hours beside a very gentle heating element.
It has been my experience that it is best to wait at least 24 hours after painting a sample before judging the color of the paint. Sometimes the color change in this time is very little, but other times it can be huge. By "huge" I mean relatively; to the naked eye the color change might not even be detectable to the uneducated eye.

Up on the wall it gently deepens the black but still gives "punch" in the white. I have not tuched the calibration. It is impossible to do that with such a small sample 0.5m x 0.8m. So for my naked eye it seemed that very bright scenes, every so littlte tilted to the blue but with basically the same brightness.
sounds great! The blueness you are seeing could actually be there. Most times when a silver paint is added to a white paint the resulting mix is a bit blue because of the silver (you can see charts of this in the C&S thread). That is why I gave you that NCS color to try - it should compensate for that blue push. You might be able to correct for this small "blue push" when you recalibrate your PJ, but I am a real believer in having as color-neutral a screen as possible.

Up really really close to the screen with a bright picture you can see millions of tiny tiny flakes shining back at you :T
That is just the way it should be. :clap:

The positive effect is more obvious if you let some stray light in. Then you clearly see that the black on the white is grey and the black on the grey is darker than the black on the white which is grey :coocoo:

Just kidding, the grey effect is very clear in romms with lack of light control.
C&S is not really an ambient light mix. it will perform better than a pure white screen, but is nowhere near as good as Black Widow for an ambient light screen.

So, anyone said that they could analyse my mix? :praying:
Not a probem. You will be getting a PM soon. ;)

PS I will try to get pictures...just have to steal the cam from my kids...
Be sure to use a tripod or other steady position to take the photos; the exposures will probably be longer than you can take by just holding the camera in your hands and still get clear shots.
 

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An undesirable viewing cone will result from too much gloss. The gloss could be coming from the base paint or the silver paint (but probably not from the reflective particles in the paint, which are almost certainly either coated mica or polyester). If brush marks are visible, they could be a contributing factor as well.

If mica flakes are coated heavily enough they will not refract light to any significant amount, but most mica-based silver paints are made with mica flakes that are designed to refract as well as reflect - we are trying to find one that is truly metallic (light reflection) with no visible iridescence (light refraction).

I'm looking forward to the samples.:T
 

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To Harpmaker ; custard ; mechman ; wbassett

Fantastic feedback on my mixes I sent. Can you post the diagrams on my thread?

I will buy another silver (with guaranteed aluminum) and another white base soon and send it to you.
Sure, I'll post them below.

The aluminum paint probably won't work for C&S, my guess is that it will darken the mix too much to make an N9, but it might be worth a try. :huh:








It should be noted that the silver paint ("Hobbylack") Robert used to make this C&S mix with is mica-based and shows a prismatic effect, the white paint it was added to completely masked any refraction so it could still be used.

Please note that the white paint has a gloss factor of 5, this turns out to still be too glossy and will hot-spot with the added silver paint.
 
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