CGIV For mech

[benven]

Hi guys, nice job on the Black Widow. Since mech was curious about CGIV, I'm gonna spill the beans. I was waiting for the gain testing to be completed but it looks like there is alot of other work that needs to be done. This is not an ambient light buster. It is a nice compromise between a white screen and a darker gray screen. I have been into darker gray screens. All of the previous CG mixes were pretty much around an N6-7. Actually, they also used a latex based aluminum product However, my taste has changed and I like a brighter, whiter screen all around. As mech has previously tested, CGIV is about an N9 shade. It's more complicated than the Black Widow, but the materials are pretty much readily available.

Here is what I mixed up.

Base coat:

240 mL Varathane Outdoor Satin Polyurethane
240 ml Behr Ultra Outdoor Flat White no 4850
20 mL of H2O, plain tap water
2 mL of Pearl Ex Silver Powder no 663

Main Mix:

420 mL Varathane Outdoor Satin Polyurethane
240 mL Behr Outdoor Flat Deep Base no 4300
240 mL Behr Ultra Outdoor Flat White no 4850
40 mL of H2O, plain tap water
8 mL of Pearl Ex Silver Powder no 663
50 mL of Pearl Ex Micro Pearl Powder no 650

Top Coat:
400 mL Valspar Clear Protector no 64675
160 mL Behr WOP no 751
160 mL of H2O, plain tap water
2 mL of Pearl Ex Silver Powder no 663

You don't have to use the base coat. You can paint the main mix right over top of a white base. The main coat is translucent so I wanted a bit darker gray shade, so I made up a gray base. You don't have to use the top coat. It does give you a bit more gain and better blacks. Like most topcoats! I have yet to topcoat my screen. I am debating whether the on axis benefits outway the off axis benefits. As with most pearl topcoats, they look yellowish off axis and obviously with the gain they provide, a little darker off axis. But blacks are better. What to do, what to do......

As you can readily see, I have used products that are made for the great outdoors. That means no yellowing over time if exposed to UV. That also means you can use this on an outdoor screen. The other good thing is, if you want a lighter or darker gray, simply adjust the amount of silver powder. Edited: Forgot to add this in my original post.

mech tested the main mix as being neutral, or really close to neutral. Warning, he has not tested the topcoat because I haven't sent him a sample. However, I don't see any issues with it based on my testing. Please see attached gray scale file. Don't worry about the top end. That is my projector. I can't get into the service menu anymore and I had tuned down red gain, the only change I had to make in the service menu, with my previous screen. A minor adjustment of red gain and gray scale would be really good. Only user menu adjustments were made. Measurements were taken about 6" from my screen, at a 45 degree angle, with an Eye One and HCFR software. The pearl topcoat measurements were taken off of a test panel placed in front of my main screen.

[mechman]

And I am still waiting for my block of Magnesium carbonate!

When it does show I'll get it done.

mech

[muzz]

Good to see ya Ben.

Looks promising, as usual!!

Keep up the good work

m

[cynical2]

Awesome, Ben!!

Thanks for posting. A few questions come immediately to mind:

• Any screenshots comparing to a comparable shade of grey?
• What tool do you use to correctly dose the small quantities (like 2mL)? Syringe?
• Some already know this (since PFG's benefits are now documented), but would you be interested in a brief comparison to CG-III? Pros/cons, etc?
• Would you consider also "spilling the beans" on any of your previous latex Aluminum based mixes? For instance, would you share what aluminum ingredient you used?

Anyway, I'm excited that you're willing to share CGIV with us...and do not at all intend on pushing you beyond your level of comfort, but you've been experimenting a long time. The more that new folks can learn from folks like you and Bill and mech, the better off the DIY community will be. It's also great to see the gathering and posting of REAL DATA.

And for all to know...I paid for the magnesium block on Jan 3rd...I just emailed the company to see what the issue is, but hopefully mech will have it in-hand soon. Sorry mech!

[benven]

Hi Jim.

I don't have any comparison shots. Just plain lazy I am.
I used small little 1 mL spoons that I purchased with the pearl powders. I was using my wife's kitchen measuring spoons but she quickly put an end to that.
Compared to CGIII, this has less gain. Therefore, larger cone. Better blacks. Whites aren't bad comapred to CGIII. I don't see that dingy yellow off axis colour like I did with CGIII.
The beans on the latex aluminum product, Createx Auto Air Aluminum Fine, I used have already been spilled. Check out the AVS archives for the original CG, dark like a Firehawk, and CG Plus. Unofficially, CG Plus was leading the pack in an ambient light shootout that never happened.

[cynical2]

benven wrote:

Hi Jim.

I don't have any comparison shots. Just plain lazy I am.
I used small little 1 mL spoons that I purchased with the pearl powders. I was using my wife's kitchen measuring spoons but she quickly put an end to that.
Compared to CGIII, this has less gain. Therefore, larger cone. Better blacks. Whites aren't bad comapred to CGIII. I don't see that dingy yellow off axis colour like I did with CGIII.
The beans on the latex aluminum product, Createx Auto Air Aluminum Fine, I used have already been spilled. Check out the AVS archives for the original CG, dark like a Firehawk, and CG Plus. Unofficially, CG Plus was leading the pack in an ambient light shootout that never happened.

Thanks, Ben. A shootout that never happened...sounds strangely like a sig I recall seeing.

[mechman]

Hey Ben,

I put this under the microscope and there are red and blue flecks(?) in it. Do you know what causes this? Is it the Pearl powder? With my eye I can see nothing but what appears to be a N9 with a little bit of sparkle to it.



mech

[benven]

Ha. You saw that too. I also see red. It's funny, when the mix is wet and I hold it under a halogen light, no other light gives the effect, I see RGB specks. It must be the pearl flakes acting like little prisms? I can also see this when dry, but not to the same degree. The good thing is no sparklies when viewing.

[mechman]

Here's the magnifications...





How did you get the mica to not act like a prism? No color shifting little prisms like I've seen in all the others. Does it have to do with the quality?

mech

[benven]

Very odd. Maybe quality of the pearl and silver powders has something to do with this. I have no idea where the read and blue spots are coming from. The mix is translucent. But I did paint the base with white paint, Behr 4850, prior to putting on CGIV.

[mechman]

Regardless, it works!

mech

[mechman]

Hey Ben! Where did you get the Varathane at? The big orange store? I went to Lowe's today (which is becoming the store of my choice due to their excellent paint department!) and all they had in the Varathane brand were for floore. They had no exterior water based poly's.

mech

[benven]

Hi mech. Yes, I bought the Outdoor Varathane at #20's store not #48's store.

[benven]

One thing to note is the Micro Pearl seems to be a much finer size of flakes as compared to the craft paint pearls. I think that is the biggest factor right there, better quality.

Even mixed in paint, unless the paint is a heavy clay based paint, or loaded with Ti02, it will have some translucent properties to it, at least on the outer surface. If it didn't, then it would just cover the mica and what would be the benefit of mica, aluminum or anything mixed with the paint itself? But paint does allow light to penetrate to a point. Aluminum will reflect the light back without any of it passing through the aluminum flake. Mica is translucent and allows light to pass through it, and when the light passes through the mica it gets refracted. That's what causes the sparkles of colors we see.

I think if a major amount of micro pearl were used then you would start seeing the iridescent effect begin. Like I said, I believe it's because this is a finer particle size that is the real key.

Can you see from the 10X shot of the Pearl Silver though that if that was added at a higher concentration than what you used color separation definitely would show up? Not a slam or anything, just my observations. Ben I am almost thinking you could drop the Pearl Silver from the main mix and not even notice. That might be a topic for the CG thread though.

For the sake of keeping things on topic, we'll continue the discussion of mica vs aluminum here.

Even mixed in paint, unless the paint is a heavy clay based paint, or loaded with Ti02, it will have some translucent properties to it, at least on the outer surface. If it didn't, then it would just cover the mica and what would be the benefit of mica, aluminum or anything mixed with the paint itself? But paint does allow light to penetrate to a point.

I think this is where we need to start our investigation. White paints are loaded with TiO2. That's why you really have to thin them down to get any sort of "gain" effects from pearl powders. Even a 5% concentration of white paint in a clear base will mute the iridescent effects of mica powders. This conclusion is derived empirically by the many mixes I have blended.

To my point, when silver mica flakes get mixed in with white paint, they only create a colour, ie gray. Much the same thing should occur with aluminum flakes. They are only creating a colour. Is the reflectance, reflective properties of these flakes muted? I believe they are. So my question is....if you make a neutral gray mix with silver mica flakes or aluminum flakes do they have different properties? Based on mech's observations under a microscope and my own keen eye I don't think there is a difference. This is not meant to be argumentative. Just a discussion so we can understand what's going on here.

As for eliminating the silver powder from CGIV, how would you get a gray mix??

[benven]

Bump. Any thoughts? Or am I out to lunch? Well breakfast right now anyway.....

[mechman]

benven wrote:

I think this is where we need to start our investigation. White paints are loaded with TiO2. That's why you really have to thin them down to get any sort of "gain" effects from pearl powders. Even a 5% concentration of white paint in a clear base will mute the iridescent effects of mica powders. This conclusion is derived empirically by the many mixes I have blended.

To my point, when silver mica flakes get mixed in with white paint, they only create a colour, ie gray. Much the same thing should occur with aluminum flakes. They are only creating a colour. Is the reflectance, reflective properties of these flakes muted? I believe they are. So my question is....if you make a neutral gray mix with silver mica flakes or aluminum flakes do they have different properties? Based on mech's observations under a microscope and my own keen eye I don't think there is a difference. This is not meant to be argumentative. Just a discussion so we can understand what's going on here.

As for eliminating the silver powder from CGIV, how would you get a gray mix??

Well, my $.02? From my empirical studies of mixing aluminum powder - not flakes - with paint, the paint does not seem to have any effect upon the aluminum. This doesn't mean I'm right or that there are not problems. There are. From what I've seen I agree with the thinning of the mix. Why? Mainly to get the paint to lay flat enough so that the aluminum spheres can shine through. Maybe I need to find larger spheres! I was trying a lot of different things with the pound of powder I have but I couldn't get it figured out. That's when Auto Air came along!

So the problems I was having with straight aluminum powder were that the paint was drying too thick and the powder was settling at the bottom. So it was a matter of finding the right consistency to counter act the negative effects of the paint. I was getting close in this regard.

And then the problem of making it neutral.


mech

[benven]

Yeah, that's my point. You said larger spheres. I think that's the key. The white paint literally covers up the powder/flakes, whatever we are calling these things, thus, eliminating any relflective/refractive properties of the powder/flake. I think we need a method to figure out if this is true or not.

[benven]

Been thinking about this for a little while. Can we not make up 2 mixes, 1 with silver mica powder and 1 with aluminum, let's say from Auto Air, and get them to within a few points on RGB. Use the same white base. Then we measure L. That should really be the only difference. Aluminum being reflective and silver powder being refractive. L should then be higher on the aluminum based mix.

It's pretty obvious to me that we can get a neutral gray from silver mica powder and from aluminum powder/paint. I'm still struggling on what the difference is, if any, between non interference and interference methods. A neutral is a neutral. So why all the fuss with aluminum? Been there, done it. I really don't see the earthshattering, real world, performance benefits. Someone please enlighten me!!

[mechman]

We can get a N9-N9.5 with silver mica powder. And it acts like a N9-N9.5 mix I'd presume. Now here's a question for you, can we get a N6-N6.5 silver mica powder mix and have it give you whites that perform like a N8-N8.5? I don't think you could. Why? Because you'd have to have so much mica that it would probably remind me of the 60's (think rainbows).

I realize you like your lighter screen but that's not really what I'd want. I want deep blacks. Blacks that an N9 can't give me. And this from a DLP guy!

And while I realize you've been there and done that, did you do with an off the shelf color? Did it have more than two ingredients? I think you're missing the point Ben. This is supposed to be easy. CGiv is easy for me and easy for you, but 90% of the folks out there don't want to have to measure ml. If we can get them something where all they have to do is buy a quart of this and throw in 4-8oz of Auto Air, case closed. It really doesn't get any simpler than that. If this has been done before please throw me a link cause I can't recall any mixes being so simple.

As for the difference between interference and non-interference, that's simple. One interferes while the other doesn't. Reflection/Refraction. Is the silver mica an interference or refractor (is that a word)? I don't know. I know I trust you well enough to know that what you have here works. And I've seen the magnification of it. I can attest that it does not appear to be anything like the other micas I've seen. Maybe it's the quality, I dunno. I'd love to see a bunch of it under the microscope sometime. I do know that you're using a minute fraction amount when compared to both previous mixes/pearl topcoats and to the amount of aluminum we're using. Percentage-wise we're at 20% and you're at less than 1 if I recall correctly. Apples and oranges.

mech

[mechman]

I should add that I think it might be difficult for us to get a N9+ screen out of aluminum at 20% of the mix.

mech

[benven]

Hi mech, this is what I am struggling with. I understand the principles of interference and non interference methods. But with all of that white paint are we really going to see the disco ball effect with interference silver powder? Would it matter if only 5% powder is required to get to an N6? As long as you get there. I am not even talking about a paint mix for the masses. Just theory here. I need to understand the difference. I hope you can appreciate my thirst for knowledge here. Isn't that what this forum is about??

And my AA solution was only AA, white paint and clear. That's pretty simple, isn't it? Can't post a link because I can't get into the AVS archives. I still have a swatch of the mix. I'll see if I can get you a picture.

[mechman]

benven wrote:

Hi mech, this is what I am struggling with. I understand the principles of interference and non interference methods. But with all of that white paint are we really going to see the disco ball effect with interference silver powder? Would it matter if only 5% powder is required to get to an N6?

I think I may need a better grasp of the silver powder. Is it mica? Is it silver coated mica? If it's the latter that would be very interesting! Are you saying that a mix with 5% silver powder gives you a N6? The aluminum's (HE558, Auto Air, and raw aluminum powder) create quite the dark mix at 20%. Does the silver powder do the same?

As for the diso ball effect, I've seen it in every mica mix I've magnified.

benven wrote:

As long as you get there. I am not even talking about a paint mix for the masses. Just theory here. I need to understand the difference. I hope you can appreciate my thirst for knowledge here. Isn't that what this forum is about??

Yepper!!

benven wrote:

And my AA solution was only AA, white paint and clear. That's pretty simple, isn't it? Can't post a link because I can't get into the AVS archives. I still have a swatch of the mix. I'll see if I can get you a picture.

We looked for it when you mentioned it and couldn't find it either. Did you check your AA mix for neutrality? When I mix AA with any of the whites I have it creates a mix that pushes blue. This includes Behr, Valspar, and Sherwin Williams. And each of these whites lacks blue on their own!

So our plan is to mix colors until we find something that works so that folks can go into Lowe's and say give me a quart of "Mech's Headache" and dump some auto air into it.

What will be interesting will be whether or not the Auto Air performs as well as the HE558. They are two very different types of aluminum!

So when I'm done with this I should pick up some silver powder eh?

mech

[wbassett]

Ben a couple things could be at play.

1. The quality of the mica.
2. The physical size of the flakes. (Partially a quality item again)
3. The amount of mica used.
4. If the mica was treated (coated) with anything to prevent light from passing through.

Quality is obvious, it ensures all the flakes are uniform in size, the density of mica flakes are the same from one batch to the next, and there are no impurities mixed in with the mica. Non-uniform flakes (both in flake size and thickness) will interact with light differently from each other as will two mixes that have different densities of mica.

The amount used, again pretty obvious, the more used, the more of the intended iridescence effect will be seen. The object covered with a higher density of mica will be brighter, but also shimmer.

If the mica is coated- This is an interesting one. I know some commercial companies do this, and there are art mica's that are coated with things like Titanium Dioxide as well as other materials. They alter the mica from allowing light to pass through (bending as it does) and being refracted. This essentially changes the properties of mica from a non-interference to an interference medium.

As far as changing the shade of white to a gray by the use of pearl silver powder or aluminum, if we can see the change in color, then we are seeing whatever was added. If it was in a very opaque white paint and not near the surface, we wouldn't see much of an effect, if the paint is translucent, or altered to be more translucent, then there would be more of the pearl silver or aluminum seen.

The difference really is how the material interacts with light. If Jacquard coated their mica, then it would be reflecting and lose the refractive iridescence quality associated with micas. The Micro Pearl does not seem to have the classic shimmer and rainbow effect seen with other micas, so it is either due to the size, or it was treated to make it reflective and no longer an iridescence. If it is still pure mica, just ground to a smaller size, it would take more to have the same rainbow effect that bigger and irregular size chunks of mica exhibit.

The effect is clearly seen though with the pearl silver. Why doesn't it show up with CGIV? Only .27 ounces is used for a 35 ounce mix. That really is a tiny amount compared to other applications. Even for non screen applications it is a very small percentage of the overall mix. If the pearl silver was increased, I am sure you would start seeing the effect. What is interesting is the Jacquard Micro Pearl.

I also noticed the archives are down over there. A pain, but no biggy. Can you give a list of your previous CG methods and how they were made? It would be interesting to see the history behind the CG application, how it came about, why changes were made, why one works better than another...

I saw reference to you using an oil based aluminum, but no mention as to how you were using it and with what other materials.

Question about your AA Aluminum test, did you use just the Auto Air fine with white paint as a test or did you combine all three? If combined, I would have opted for a base test first with just the white and aluminum to see what that did. Also what did you use for your white base?

Black Jack (which is very very similar to AA) is extremely bright and a powerful medium to add to paint. It was showing promise, but deemed not worth spending time on since it was discontinued. Adding it to Kilz2, which is within specs as a neutral white, it did lean blue because of how strong the aluminum acts. When added to a warmer white it was coming down in tone. In hindsight I wish we would have continued with those tests because it probably would have worked with AA too. If I recall, the Black Jack/Luminous White came in much better and although not neutral, it was within the fringe of the acceptable tolerance.

So back to the topic of this thread and your question, part of it has to do with the amount used and how strong it is. I sent mech a Designer White chip painted with Black Jack 5168, maybe if he has time he can get a 10x shot of that sample. Reason I say 10x is because that's the same magnification we have of the pearl silver. Then they can be compared side by side visually and we can see a bit more of any differences or commonality between the two.

I agree, this is an interesting topic. You mentioned/asked

benven wrote:

As for eliminating the silver powder from CGIV, how would you get a gray mix??

That part is easy.

One way would be to start with a known neutral gray in the desired shade.

That's not very interesting though as far as this discussion. Here is something that may be interesting though...

Designer White is one of the undisputed premium DIY white screens out there. Thing is... it's not white. It's actually more of an N9.25 shade of gray, which is a very very light gray. Most would consider it white, but as we know, technically anything not 255 255 255 is not white, but rather a shade of gray.

With that in mind, we have a 'white' that is actually light gray. I would be interested in testing the Behr Outdoor Flat Deep Base no 4300 and Behr Ultra Outdoor Flat White no 4850 combination. My bet/guess is we'll see something around an N9 shade, but I can't say that with certainty until it is actually tested and a color reading done. Depending on what that color balance comes out to be will give us an idea of how much the .27 ounces of pearl silver is changing the shade. Maybe it is a very strong medium like aluminum and a 'little dab'l do ya', but we're speculating right now and I really dislike speculating other than for developing a working theory. After that, it needs to be tested to either confirm or disprove the theory.

What will be very interesting is hearing your thought process during your development of this and how you determined the precise amounts used. Like I mentioned, it would also be very interesting to hear the history behind CG from start to CGIV and why you made changes and moved on from one to the next.

benven wrote:

I hope you can appreciate my thirst for knowledge here. Isn't that what this forum is about??

Yepper! That's exactly what we want to be about.

My belief is we can't move on and build on anything unless we understand why current applications act the way they do. Again, this is very interesting for us DIY developers, I'm sure not so interesting for the person just looking for a screen.

Fun stuff!

[Harpmaker]

This seems like the right place to put these. If not delete them.

Two 200x microscope photos of a mix of Behr ULTRA Deep Base (flat) and Liquitex Iridescent Medium 2:1 sprayed over a flat black base coat.





Two pics of the same mix at 60x.




I haven't tested either the Deep Base or the LIM by itself yet.

Two 200x shots of TV-WM/He558 5:1 for comparison.

[benven]

Original Canadian Gray using AAA:



Never tested because I didn't know anyone with a spectro. Is it neutral? No. Did it matter back then? No. Some interesting comments about the mix though.

No use going into the history. Let's just say that this was the first mix, that I know of, to use a pigment free solution in the DIY world.

I'm still thinking that there is no difference between the silver mica and aluminum paints/flakes. I'll wait patiently for mech to finish up his work and get the silver powder so he can test the theory.