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Discussion Starter · #1 ·
The purpose of this thread is to compare the latest silver fire formulation to other diy methods to see how it holds up. If you do a comparison of your own, feel free to add it. :T We intend to compare it to several, cheaper alternatives. This first post will be a place keeper for the data on SFv2 3oz.

Spectro analysis



Gain



Grayscale and Gamut readings

Have yet to be performed. But when they are I'll put it here.

The Contenders

The first contender will be the neutral gray tint Gray Screen (Sherwin Williams SW7071) in an eggshell finish. We've done a little bit of work with the eggshell finish and have found that the myth (hot spotting) surrounding it seem to be false. Paint used was PPG Grand Distinction.​

The second contender will be a sfv2-3oz color match in satin finish. We selected the color based upon the numbers from the spectro analysis and identified a Sherwin William color that seems to exhibit the same characteristics as sfv2-3oz. Paint used was PPG Grand Distinction.​



We'll fill in more as we get to them. I know of at least two possibly three other things that I am planning on trying. And I believe Harp has a thing or two that he's gonna test out. :T
 

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Discussion Starter · #2 ·
SFv2 3oz vs Eggshell

This comparison will be to a PPG Grand Distinction Eggshell finish paint tinted to SW7071 (Sherwin Williams Gray Screen)

Spectro Analysis

Coming soon

Gain



Grayscale and Gamut

Coming soon



Pictures

In the pictures there are three separate samples. The small sample is SFv1 Lite. It was made by jinjuku. The large sample on the left is the Eggshell finish gray. SFv2-3oz is on the right side. A couple of things to note is that the SFv1 Lite sample is the darkest of the three, then SFv2-3oz and finally the Gray Screen panel. There are 8 photos all from 4 different angles and each angle having 2 shots - one with a moderate amount of ambient light and one with no ambient light at all. The angles are on axis, ~15 degrees, ~40 degrees, and ~65 degrees.


















Conclusions

In the photos above it is clear that SFv2-3oz has a serious problem with viewing cone. While the eggshell panel does not. On axis, SFv2-3oz is very bright. But moving the camera over about 4 feet clearly shows the change in the luminance of the panel. The Eggshell sample is brighter from there on out. Comparing two angles, 0 and any of the others, almost makes it seem like the eggshell panel is a much darker shade of gray in the on axis shots. But it is the same all the way across.
 

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Discussion Starter · #3 · (Edited)
SFv2 3oz vs Satin

Spectro Analysis



RGB 170 176 178
LAB 71.3 -1.77 -1.83

Pretty nasty blue push on this sample. The sample used was SW7072 Sherwin Williams Online. Number wise it should have been a close match. But one never knows what the paint mixers are going to come up with. This was a PPG Grand Distinction brand of paint mixed at Menards.

Gain



Grayscale and Gamut



Pictures

The Satin panel takes up roughly two thirds of the left side. Silver fire version 2 is on the right. First picture is with ambient lighting. Second image is darkness. First two images are on axis, second set is ~15 degrees off axis, third is ~30 degrees off axis, fourth is ~45 degrees off axis and the last set is ~60 degrees off axis.

***EDIT*** There are no 45 degree shots. I think my brain hiccuped for a moment. ***EDIT***



















Conclusions

The satin sample is pretty much on par with the sf sample on axis for brightness... in the center of the image. Looking at the left side you can see that the whites are a bit dimmer. This is a classic example of hot spotting. And this is clearly evident as you move off axis on the satin panel. The satin panel hot spots slightly more than the sf panel. One thing to keep in mind though is that the satin panel is darker than the sf panel. The L value is 73.8 for sf and 71.3 for the satin sample. It should look a tad bit darker off angle

Looking at the blacks in ambient lighting, the winner is an easy to distinguish - the satin panel.
 

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Discussion Starter · #4 · (Edited)
SFv2-3oz vs GSEgg:LBS 1:1

Spectro Analysis



RGB 198 201 199
LAB 80.7 -1.38 0.53

The paint used for this is PPG Grand Distinction Eggshell finish tinted SW7071 Sherwin Williams Gray Screen. This was mixed at a 1:1 ratio with Liquitex Basics Silver.

Gain



Grayscale and Gamut



Pictures

For this set, the Eggshell:LBS 1:1 sample panel is on the right two thirds, with sf taking up the left third or so of the test area.


















Conclusions

This test panel is what I would consider a sf-killer. Whites on axis are slightly better than sf. Blacks in ambient lighting are slightly better on the sf panel. So why take the test panel over sf? Because the test panel would cost about 1/4 of the price of a sf screen. Quart of paint would be $10 and about $15 for the Silver paint. Plus, while I didn't roll this panel, I'm certain it could be rolled.
 

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Discussion Starter · #5 · (Edited)
SFv2-3oz vs Satin:LBS 1:1

Spectro Analysis



RGB 173 178 179
LAB 72.3 -1.66 -1.12

This panel consists of one part of the satin paint above (SW7072 - Online) and one part Liquitex Basics Silver. Again, this panel is darker than silver fire so keep that in mind as you are looking at the pictures.

Gain



Grayscale and Gamut



Pictures

The Satin:LBS panel is again on the right side with the silver fire panel on the left two thirds.

















Conclusions

From the photos above it appears that the Liq Silver seems to have an easing effect on the hot spotting witnessed with the straight satin paint only panel. The whites are brighter on axis with the panel getting slightly dimmer near the right edges. Blacks are definitely blacker on the sample panel than sf. As you move off axis the sample panel still retains the white edge over sf except on the first off axis shot. I think that one may be another camera anomaly though due to the WhiBal card. If you look at the card it's reflecting quite a bit of glare from the projector.
 

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Discussion Starter · #6 · (Edited)
SFv2 vs matched colorant

SF v2.0 versus a matched color component

This post is meant to debunk some of the most ridiculous things you've ever read about screen paint. Here's a quote someone sent me about this particular topic:

the colorant is really individualized color components and each mutually exclusive of each other. suspended side by side in a translucent solution, the totality of the mix appears to grey, but the individual components (RGBY) each react differently to the light being projected. very much unlike how white reflects ALL colors the same and black/grey both reflect and absorb all colors the same dependent on shade.

so to make a long story short... what you have proposed is essentially what RS-MAXXMUDD already is... minus the additional LAMP BLACK that would be added by having the store try to color match the components.

and that in fact, would make substitute SF mix less than RS-MaxxMudd.
This post will contain the proof that the above statement and many others similar to it are utter nonsense. Panel will be sprayed tomorrow. Color matched color component cost a whopping $3 as opposed to $20+.

Measures



As you can see, the color match has a Delta Error of less than 1. Most paint stores would consider a anything with a DeltaE of less than 2 a good match. About the only thing I am worried about is that this will fix SF2.0's color issues. :whistling:

Spectro Analysis

I didn't get to this yet. I did a preliminary measure of the new panel last week and I recall it had a slight red push to it. It was about on par with the blue push from sf v2 3oz. I'll have it done by the weekend though and I'll post it here.

Gain

Grayscale

Pictures

There are 4 separate panels in these shots. Two of them are just for more comparison. One of the extras is the 1:1 VUP Eggshell:Liquitex Basics Silver and the other is a test I did using an N6 paint with polyurethane and Liquitex Basics Silver. The first image shows the placement of the panels.











Roughly 15 degrees off axis:











Roughly 45 degrees off axis:











Roughly 60 degrees off axis:













Some high ambient light shots:







Misc shots:



















While taking these pictures, I was laying on the floor in front of the screen with multiple remotes laying around me. From my viewpoint, the N6 conglomeration was performing better than both sf v2 and the color matched sf v2. In order to show that I took a few pictures from where my head during this test. While the color balance is off on the N6, it's amazing to me that it has an image that is on par, brightness-wise, with sf v2. I think that is further proof of the terrible viewing cone and horrendous hot spotting of the silver fire mixes.





 

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I'm curious as to why the SFv2 "looks" brighter in the 0° shot over the SW gray. Yet they have nearly identical gain readings at the 0° position.

Are the gain readings a misrepresentation (not intentional by the measurer I must add:T) when dealing with a DIY paint that is heavily laden with metallics or mica?
 

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Discussion Starter · #9 ·
I'm curious as to why the SFv2 "looks" brighter in the 0° shot over the SW gray. Yet they have nearly identical gain readings at the 0° position.

Are the gain readings a misrepresentation (not intentional by the measurer I must add:T) when dealing with a DIY paint that is heavily laden with metallics or mica?
That is something that I wondered myself. And I have to admit that I was a bit flummoxed at first. :dontknow: But I figured that it had to do with the camera focusing on the center of the shot and the amount of light it let in from each panel. I think it has more to due with the pictures being a misrepresentation of the gain. :T
 

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Just a general FYI, proper gain measurements are taken using a white reference target (sometimes called a Unity target) that is totally diffusive in reflection (has NO gloss whatsoever) and is as close to a pure N10 white as possible. There are several materials used for this purpose, magnesium carbonate being one of them, and that is what we use.

In practice, for every angle tested a reading is taken of the reference target with a 1° spot meter and the reflectance written down. Next the screen under test is swapped for the reference target and another reflectance reading is taken. The ratio of the two readings is the gain of the screen and is given in percentage.

If a white screen has a gain over 1.0 then it must be achieving the additional brightness on-axis by taking brightness from off-axis. The same applies if a screen has a gain of 1.0, but is darker than pure white.

Any time a gray screen is said to have a gain over 1.0 be skeptical that either the gain figure is wrong or the screen will have viewing cone problems. You can Rob-Peter-To-Pay-Paul only so much before viewing cone and/or hot spotting become real issues.

All this applies to commercial screens as well as DIY.
 

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Discussion Starter · #11 ·
I updated the titles to reflect some of the tests I'm going to run. You'll notice the second to the last one states SFv2.0 vs SFv2.1 because as has been the case since we've run these tests, the formula did, in fact, change. Fortunately, I have enough supplies to mix up a few more batches if need be. :T
 

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That is something that I wondered myself. And I have to admit that I was a bit flummoxed at first. :dontknow: But I figured that it had to do with the camera focusing on the center of the shot and the amount of light it let in from each panel. I think it has more to due with the pictures being a misrepresentation of the gain. :T
I can agree with this to some extent, because the Eggshell actually appears to get brighter as you move off-axis which obviously is not the case.

Update: I just noticed that the exposure is not the same in the off-axis shots which is why the eggshell finish appears to get brighter as the angle increases. Compare the shadow on the movie poster to see what I mean.

Update2: I updated my post to reflect comparing SF2-3 to my Elite MaxWhite screen. That screen was measured by an AVS member to be 1.03 at 0 degrees and .99 at 18 degrees. MY SF2-3 is definitely dimmer than the Elite screen, so I think the SF2-3 gain readings are inline with that other person's measurements of my MaxWhite screen, at least within 0.05 gain by my entirely subjective measurements :).
 

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Discussion Starter · #13 ·
Yes the camera was set to 'auto-everything' with the flash shut off. That's why I suspect the camera. But who knows? :huh: When I do get time, I'll put it all back up with the MgCO block and snap a picture. The key words though are 'when I do get time'. It seems like something is always coming up lately. :foottap:
 

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Discussion Starter · #14 · (Edited)
I did a little experimenting with exposure.

f10 - 1/2 sec - ISO 500



f4.6 - 1/3 sec - ISO 500



The shot in the eggshell post was shot at f4 - 1/3 sec - ISO 100

This is all I could get done at the moment. I'm going to try and get a few more shots later this evening.

Also, I have sprayed all the panels for comparisons. :T Should be able to get all the photos and data this upcoming week.
 

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I think you are getting closer with the pics, but you have to be careful of highlight clipping. The white areas are all perfectly white 255 in the 2nd picture. I think the first one is closer to an accurate exposure, probably only 1/3 to 2/3 of an f-stop underexposed.

That is an Elite Gray screen underneath right? The eggshell is really close to that in appearance.
 

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Discussion Starter · #16 ·
I think you are getting closer with the pics, but you have to be careful of highlight clipping. The white areas are all perfectly white 255 in the 2nd picture. I think the first one is closer to an accurate exposure, probably only 1/3 to 2/3 of an f-stop underexposed.

That is an Elite Gray screen underneath right? The eggshell is really close to that in appearance.
Yeah I'm getting there. I must have been centered up on something other than the sf in the first on axis shot.

Yes it is an Elite CineGrey. I'd say they are pretty close.
 

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I'll be interested in the gain readings of the LBS samples. Especially that satin one. It does appear to hot spot, BUT, the off axis shots seem to be consistent, even though they are getting darker. To me the 15° looks the same as the 60°:dontknow:

How grainy is that LBS anyway? Does it color shift the paint much?

What would happen if one were to use a neutral white and use the LBS in a 2:1 ratio?:sneeky:
 

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I'll be interested in the gain readings of the LBS samples. Especially that satin one. It does appear to hot spot, BUT, the off axis shots seem to be consistent, even though they are getting darker. To me the 15° looks the same as the 60°:dontknow:

How grainy is that LBS anyway? Does it color shift the paint much?
Mech does all the gain stuff.

LBS has a very fine grain since the mica particles are very small, but it is mica and it does refract light like it's larger grained cousins in the craft paint aisle. The secret to making a screen mix with mica that doesn't color-shift is to use enough opaque paint in the mix to control most of that refracted light.

What would happen if one were to use a neutral white and use the LBS in a 2:1 ratio?:sneeky:
It pushed blue, but not as much as other silver paints. I did have to develop a base color to correct it enough to comfortably fit within our neutrality standards when developing the new C&S™ Ultra mix (which is tinted Valspar white enamel and LBS mixed 1:1).
 
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