Here's some data from some testing I did tonight.
I did all the maximum cd/m2 tests without touching the meter between materials. I then lowered the meter aproximetely 25 or 30 degrees for another cd/m2 reading and ran all the materials through again, also without touching the meter between readings. I used an Eye1 Pro and HCFR. I used BabelColor CTA and the Eye1 Pro for the color data.
The first number is cd/m2 with the sensor adjusted for maximum reading. The second number is cd/m2 with the meter lowered about 25 - 30 degrees. the third fourth and fifth numbers are the RGB values. The last number is deltaE from perfect neutral. A deltaE of less than 1.0 is considered perfect. Less than 3.0 is considered to be so close as to be indistinguishable from neutral by the human eye, at least according to what I've read.
I've included readings from my SF HG screen for reference. Check this thread:
http://www.hometheatershack.com/for...esting/51685-titanium-sintra-development.html and you can see the hotspotting on that screen. Then note the variance between cd/m2 high and low numbers. I've included some data from some Cream & Suger paint that I have. Please note that we have determined that the sample I have is a first version, and not representative of C&S in general. There were most certainly some issues either with the base or the silver paint. But you can see how it's possible to have ZERO variance in cd/m2 for normal viewing angles. The cost, of course, is low gain.
Titanium Sintra:
37.5 32.2 246,246,242 2.36
Glidden Diamond 450 Titanium White:
36.35 31.6 245,246,243 1.43
behr 1850 UPW:
35.3 32.05 249,249,246 1.95
Sherwin-Williams ProClassic Smooth Enamel Satin Extra White:
31.25 29.5 240,241,236 2.58
Carrada Brilliant White 1.4 Gain:
36.1 30.8 242,242,236 3.22
C&S:
22.6 22.5
SF HG:
33.1 22.5
One note: This really opened my eyes. Comparing the Behr and the Glidden visually, I would have said the Behr is slightly brighter. The slight color variance can fool the eye; it really truly takes instrumentation to tell the tale.
Visually, I can detect absolutely no hotspotting with the Glidden, Behr, or SW. The Carrada sample is too small for me to really tell. The Titanium Sintra is possibly warm in the center. I don't believe a full screen would show a hot spot, but I guess it's possible. I just don't have the experience to tell for certain.
I wanted the Titanium Sintra to be the clear winner, but I can't say that it is right now. I think the extra 3% brightness it has over the second brightest paint--the Glidden--is worth investigating. (At least for me.) But it isn't there yet. The Glidden is only 3% dimmer, and is off the shelf and easy to apply.
Personally, I think the Glidden and the Behr are both better choices than the Carrada BW sample I have. Similar gain characteristics and more color neutral. I'd give a slight nod to the Glidden over the Behr, and I'd rate the Sherwin Williams a distant number four. Distant at least when you consider how close the top three are.
So, here are my ratings:
#1 Gliddon Diamond 450, Titanium White, Velvet Matte
#2 Behr UPW 1850, Interior Flat Enamel
#3 Carrada Brilliant White 1.4 Gain Manufactured screen.
#4 Sherwin-Williams ProClassic Smooth Enamel Satin Extra White
Titanium Sintra: Not ready for release.
BTW: I did do reflectance curves of all the white paints, they are all equally good with the Behr being the brightest white, N9.78. I'm just too lazy to post the graphs.
:blush: