Pearl Clear Coat Trials

[Tiddler]

Decoart vs Folkart, 2xPearl, 2 Coats

The base layer is the same matte neutral gray paint. Each Pearl Clear Coat represents 2 2oz. bottles of Pearlizing Medium in a quart of Behr Matte Polyurethane #780.

The photos were all taken with moderate ambient light in the room.


Except where indicated, the Decoart sample panel is on the left and the Folkart sample is on the right.

Black % White Bars

On Axis the Folkart sample is brighter.
I also noticed that the white is a cleaner whiter white. The Decoart seems to have some very slight color shifting.
I am concerned that at about 30 degrees the Folkart sample is quite bright and the Decoart is not.
This seems to suggest that the Folkart would not have a very uniform brightness across the whole screen.
This seems to be confirmed in the third shot where the Decoart is brighter and the Folkart is significantly darker.
At about 45 degrees the two pearl samples are not quite as bright as the EasyFlex-06 retractable screen.


In these photos I threw some white light at them.
First from the computer, then the DVD player, and then used the flash.

It looks like there is some warm spotting.

Here is a closeup of the Decoart (left) and Folkart (right).

There is no appearance of apparent surface sheen. It is not as bad as the Behr Eggshell shown in the third photo.

Generally I would say the Folkart Pearlizing Medium produces a whiter brighter image. It seems to have a higher concentration of mica flakes than the Decoart.

My inclination would be to use the Folkart Pearlizing medium in a 1.5xPearl concentration for three coats and then apply one matte poly top coat. I will be trying something close to that with my next sample. It will be three coats of 2 parts Faux Glaze + 1 part matte poly + some eyeballed amount of Winsor & Newton + Liquitex Iridescent medium. If this looks promising then I will duplicate it more accurately using the Folkart Pearlizing Medium.

[Tiddler]

Decoart vs Folkart 2xPearl, 2 Coats

Here are some screen shots from T2. The Decoart is on the left and the Folkart is on the right except where indicated:

Some Dark Scenes:


Brighter Scenes:


Her Face Closeup:
. . . .. . . .. .
| Decoart <=> Folkart || Folkart <=> Decoart || Folkart <=> Decoart |

Kids Face Closeup:
. . . .. . . .. .
| Decoart <=> Folkart || Folkart <=> Decoart || Folkart <=> Decoart |


Truck 7 Distruction:


Comments:

As I indicated in the last post the Folkart Pearl seems to produce a cleaner whiter white. It also seems to have a higher concentration of mica flakes than the Decoart. Therefore at this time the Folkart appears to be a better source of mica flakes. Both samples do exhibit a tendancy to warm spot that would likely result in a nonuniformity across the screen.

The next trial will involve 3 coats of lower concentration and a final matte poly top coat. I am hoping this will result in a more diffused gain boost and the final top coat should eliminate any chance of surface sheen.

[wbassett]

The Folkart is looking good. The whites look clean and white and the detail doesn't look soft.

One thing that caught my eye was in the now classic hallway scene, (if anything is going to hot spot, that scene will) the window on the Folkart panel- Look at the lower window panes where the trees are. You can actually see the security wire (chicken wire) in the glass. That is pretty amazing detail.

The over all look is cleaner too. The walls look brighter and whiter. It's interesting that the main screen looks just fine when viewed on it's own, everything looks white and clean, but these shots are actually showing some limitations in the main screen. Todd you may end up painting another retractable screen if you keep this up!

Great work. I know you and I had this conversation last year about optical coatings and it's good to see it finally getting the attention it deserves/requires. I really think we have the base colors down now and the logical step was to refine the clear optical coatings. Your work is definitely showing things are going in the right direction.

Some may argue this takes an application from simple to complex, I disagree. Once you work out the fine details for application this is a nice two step method. A person can start with a simple gray base and get a screen up very quickly and at a comfort level they don't feel overwhelmed with. From there they can decide whether they want to apply step two, but there is no rush and they can do it whenever they feel comfortable. Some may opt to do both steps right away, others may wait, and then a certain percentage of people will decide to stay with the base coat. So all in all this is a very nice progressive way a person can approach a DIY painted screen application.

When you finally get the optic coating tests done, let's make a refined application thread on clear optic coatings and we'll sticky it. One of the great things about this method is it isn't restricted to just painted screens and doesn't involve complex mixing for a collapsed layered method. The more variables and components required, the more chance for error. This is definitely simple and going in the right direction in my opinion.

(Chicken wire security glass- I have a story about being a stupid kid and security glass... but that is more of a topic for 'The Idiodic things we do as kids! )

[wbassett]

tiddler wrote:

In these photos I threw some white light at them.
First from the computer, then the DVD player, and then used the flash.

It looks like there is some warm spotting.

The big thing is can you tell when a movie is playing?

The center of the screen is always going to have the highest fL of light since that is where the projected light beam is centered. Unless it is visible during live action I don't think I would worry about it. You're bound to see things on still shots and detailed analysis that you normally wouldn't notice. True if it can be eliminated all together that's ideal.

Don't give up on trying to eliminate it, I'm just saying unless it's noticeable during playback it may not be an issue.

The on and off axis shots do show a reduced viewing cone, but we did expect that, or should have.

On Axis the Folkart sample is brighter.
I also noticed that the white is a cleaner whiter white. The Decoart seems to have some very slight color shifting.
I am concerned that at about 30 degrees the Folkart sample is quite bright and the Decoart is not.
This seems to suggest that the Folkart would not have a very uniform brightness across the whole screen.
This seems to be confirmed in the third shot where the Decoart is brighter and the Folkart is significantly darker.
At about 45 degrees the two pearl samples are not quite as bright as the EasyFlex-06 retractable screen.

This also supports that it's a higher gain and lower viewing cone. Your main screen is a matte surface closer to a unity gain and the Pearl coatings are not going to be totally uniform across the screen. What is interesting is at 30 degrees the Folkart is brighter... is it brighter at 30 degrees off axis than it is on center, or just brighter than the Decoart at 30 degrees?

If it is brighter off axis than on center that's suggesting the mica isn't reflecting things back to the viewer in a uniform way. (By the nature of the Pearlescent and mica flakes it will have a random orientation) This could help with rejecting ambient light away from the viewer, but honestly if that is the case I'm not sure how we can control the orientation of the flakes. If it's brighter on axis, then I'd say it just has higher gain than the Decoart and that's what we're seeing.

Again by the nature of their composition, mica flakes reflect light and allow a certain amount of light to be passed through. Some of it is reflected back as it should be and some of the light travels through the mica and is lost in the back of the screen (I say lost because each time the light passes through a flake its intensity is reduced- eventually it will not have enough energy to make its way back through all the mica flakes and back to the viewer) while another part of it is reflected back at a different angle. As multiple flakes are layered this effect is compounded. This does diffuse the light, but there is also a random effect as well as lost energy. This is not a defect of pearl mica flakes, in fact that is how they are designed. The way the mica flakes reflect, refract, and diffuse light gives the appearance of depth due to multiple layers and color shift. Color shift is caused by the light slowly losing its energy, and energy can be related to frequency. If the frequency changes, the light spectrum is changed, even if it is ever so slight, there is still a change.

Man-made Pearlescent are made from the mineral mica. The mica is processed into small particles and then coated with a very thin layer of titanium dioxide. The layer is so thin that it actually transmits light(allows light to pass through it) instead of acting like a normal pigment when it is used in paint.

Depending on the quality of the mica and concentration, it could also create a softening effect on the image. The better the quality of the Pearlescent, the higher concentration of mica flakes and their composition. High concentration of mica flakes doesn't always mean a positive thing though, especially when it comes to projectors and screens. Each flake is reflecting some light, and refracting some of the light. The more flakes, and with a higher lumen projector the screen can start to get sparklies. Also with more mica content, more refraction is taking place, think of it as a combination of mini prisms... With lower lumen projectors the light is mainly refracted and diffused and energy/efficiency is lost. So it's a balancing act as you are seeing and working out.

Aluminum Dioxide is another way to go instead of mica, especially for higher Lumen projectors. It doesn't refract the light the same way mica flakes do so you can get a brighter image without the need to raise the sheen, plus any potential color shift is reduced. That's just an idea for maybe some future tests that you or anyone may want to undertake. Again, I really think you're going in the right direction, and everything is building on previous work and research.

I'm playing around with a few things right now but it's off topic for in here. I think eventually everything that we all are working on will be pulled together I'd say right now our foundation is very solid and the first floor is coming together very nicely!

[Tiddler]

Here ia an attempt to demonstrate the variation in rightness with viewing angle.

I started by leting the camera decide on settings for the retractable screen with white light projected. Then I set the camera in manual to lock the settings. I the took picture of the retractable alone and with the Folkart sample panel in the four hanger locations. This should give some indication of brightness uniformity and viewing angle characteristics. I Think?

On Axis:






45 Degrees Off Axis:






30 Degrees Off Axis:

[titch--]

Really good stuff tiddler, and some really in depth ( for me anyway) read there wbassett. cheers guys.

Man its really nice to see people doing things without other people jumping inand saying this aint right, you should be doing it this and so on.

cheers again

[mechman]

It's definitely a brighter image! But at what cost? Looking at this image and where I circled it appears at the cost of blacks:



What does it look like in person Todd? It doesn't appear to be that much of a hit on the black and white bar shots. Was this one taken in the moderate ambient light? If it was could you retake it in the dark? If it doesn't take a hit in the dark than maybe this is just lightening up the gray? Just pondering out loud...

mech

[Tiddler]

mechman wrote:

It's definitely a brighter image! But at what cost? Looking at this image and where I circled it appears at the cost of blacks:

What does it look like in person Todd? It doesn't appear to be that much of a hit on the black and white bar shots. Was this one taken in the moderate ambient light? If it was could you retake it in the dark? If it doesn't take a hit in the dark than maybe this is just lightening up the gray? Just pondering out loud...

mech

You make a good point mechman. I already applied a poly top coat to the sample panel though. It does look different but I have not tried it with the projector. The poly top coat toned it down some. I know in the past when a similar shade of matte gray with a poly top coat was compared to other metallic mixes the differences were minimal. It may also be true of the pearl clear coats. The one thing I know for sure is the mica flakes don't care where the light comes from. If ambient ligt hits the screen it will be reflected.

I'm feeling a little under the weather tonight but soon I will try to investigate this question.

[mechman]

Have some chicken soup and let this go till you feel better! We can wait!

And since I cannot find a 'get well' smilie, I give to you...

the dance banana!




Hope that makes you feel a bit better!

mech

[Tiddler]

I took the sample panel with the two coats of 2xPearl-Folkart and applied one coat of just matte poly. The idea was to eliminate any possibility that the Folkart Pearlizing Medium had added sheen to the surface. As I have said before anything other than a very low luster sheen is the enemy of rolled DIY Screen Solutions.

30 Degrees Off Axis:
|. . Before Poly . .| |. . After Poly . .|






It appears to have muted the warm spot between the first and second position.