Originally Posted by Darthprater
Guys, I’ve had my 790 for about 6 months now. I’m projecting onto a 140” Severtson white 1.3 gain screen. My room is completely light controlled. I feel a bit disappointed with the black levels that I’m seeing. Even when the projected image is all black, I’m still seeing a large amount of just gray. Are the “OLED-like” black levels just blown out of proportion?
Btw my ceilings are black, walls are dark gray and the carpet is a burgundy color. I can understand that there will be some reflections, and I have black velvet that I’m getting close to putting up on the back wall and first 6 feet of the side walls/ ceiling, but like I said, even with al all-black screen being displayed, it is like an edge-lit LCD screen. Not really black.
Also, there appears to be some vertical streaking on lettering when the screen has a black background...is this normal?
Yes, OLED like black levels is a massive exaggeration. Even with the best room in the world the optical ANSI contrast of the projector light engine is somewhere under 300:1, and the black levels achieved even in full off are much, much higher than those of an OLED. Couple to that the fact that many good projector rooms are black holes, yet OLEDs are more often used in rooms that are not perfectly black, and you are further increasing the disparity between the observed blacks and their surroundings.
I find the worst scenes visually are actually murkier scenes with low APL; because in these scenes the eye's adaptation, without there being any other strong light in view, is able to allow the black of the screen wall to really make the projected grey of the image stand out. Note when I say "worst" - these scenes still look much better on a JVC than most other projectors (save for dual-modulation beasts), but OLED they're certainly not.
You can of course improve the projected black by closing the iris. If you have the means to calibrate, setting your SDR peak to 48 to 56 nits using the iris might let you close the iris and get a proportionally darker black than you otherwise would have. Running in high lamp if you don't already would allow you to close the iris further for the same peak output, again getting you a better black level for the same peak white. However it is unlikely to make a huge difference; you can see in the attached chart that the eye is able to adapt over time to see some phenomenally dark levels.
Vertical streaking is par for the course.