I'm totally comfortable posting..just worried in the back of my mind that the reason side-by-sides like this seem rare is because they magically instigate a perma-ban or some other horrible wrath. I've never seen anything mentioning it as against any rules, so it should be fine.
Like I said, nothing major here. Just some very simple comparisons that deal with black/white-levels, gain, contrast and viewing-cone on a rough level using a chunk of one of my screens that I hacked off and brought with.
-The top/left is 1partMetallic:2partsFlatBlack while that's the 1.4 below it on the bottom/left.
-The bottom/right shows the on-axis gain difference of (lowest to highest) 1partMetallic:2partsBlack, 1partMetallic:1partBlack, BlackDiamond 1.4, 3partsMetallic:1partBlack
-The other three are different angled shots showing the relative shade of the screen materials in soft ambient-light with no projected image. The 1:2mix is always darker than the ScreenInnovations and the 3:1mix is always lighter, but the 1:1mix is quite a close match.
The half-n-half mix is relatively close to the BD1.4 in some respects, but it IS slightly lower gain in order to have slightly wider viewing-cone and better uniformity when using 1:1-1:1.5 throw-distance projectors as well as to keep shimmer/sparkles minimized (despite being a rolled-on paint mix) since that was something that always somewhat bothered me about the BlackDiamond. On the other hand, the BD1.4's narrower viewing-cone should technically allow it to reject ambient-light from a wider array of angles.
It's more about picking what's most important to you and your situation than picking a clear winner.
Because it is still possible to make the highest-gain mix have a darker surface in ambient light, that will probably be my next test. It should allow for a screen that's every bit as dark or darker than the BD1.4 while still matching its on-axis gain. Making the screen with a slight curve should solve any possible issues with left/right dimming and brightness uniformity, then all that's left will be working to perfect the viewing-cone for seating arrangements of roughly 10ft-14ft width.
Because the store was kind enough to let me use my own projector for this, I was also able to take a decent collection of pictures of certain scenes using the same projector, distance/size, angles, camera, and roughly the same lighting as I've been using for everything else. So there's also groups of straight VS angled shots using the same scenes (and occasionally a white sheet in the same shot as well) using the 1:1, 3:1, 2:1, and BD1.4 screens. But, none of these are directly side-by-side, so they are of much more limited value.