.NET Solution Architect
Hi Peter, yes I've noticed that issue on my VW760ES when were calibrating 3D Lut via LightSpace.Hello,
I wish you all the best for the New Year.
I would like to point out a little peculiarity when measuring the laser projector VW760ES with the Radiance Pro. Presumably it will be the same with the VW870ES and VW5000ES.
It is well known that these projectors perform laser dimming and, when set to "Laser Dimming = Full", turn off the laser completely when a black image is displayed. To measure the dimming effect, you usually use a black pattern with a pixel that is not black to prevent the laser from shutting off completely. With the VW760ES, the dimming improves the black value by about a factor of 1.5.
But I do not think it is known to all that the laser of the VW760ES also reacts to test patterns that are not completely black even with the setting "Laserdimming = Off". A single non-black pixel is enough to increase the black value by about 12%. This behavior of the VW760ES has not changed in the current firmware 8.004.
If you are prepared for the effect, you can see it quite well with your eyes. Of course, a Klein K10A reacts immediately. There is a small effect on the gamma curve in the lower range of 0 to 15%. This is certainly of little relevance for practical film use, as a picture is seldom 100% black.
But you should always know what you measure.
If the Radiance Pro is used as a pattern generator, it always shows the letter "A" in the upper right corner for a few seconds when calling a pattern. The Klein K10A is done with black measurement before the letter "A" disappears. This letter and the non-black pixel in the "black pattern" introduced since version 100118 cause the VW760ES to raise the black value.
If you take a "neutral" pattern generator instead, such as the DVDO TPG, then you measure a black level that is around 12% low.
If someone has a VW760ES and the Radiance Pro, he can very easily check the "effect" in a dark room by manually calling up the black test pattern on the Radiance Pro via the menu, switching off the info with the "2" button and then use the arrow keys "up" and "down" to switch the "special pixel" in the upper left corner to "black" or "not black". For the first test you should set the laser dimming on the VW760ES to "full", because then the laser completely shuts off, if the "special pixel" is switched to black. Then you get a feeling how to use the arrow keys. On the second test, the laser dimming will be turned off, and then you can see with your eyes that the black level changes slightly when you switch the pixel.
Perhaps it would be possible for Jim and Patrick to offer a switch for a "completely neutral" output of the patterns, but of course that's a big hassle.
Right now I'm helping myself by connecting the DVDO TPG as a pattern generator to the Radiance Pro's input and then measuring when logging the black value is important in the context of a LUT.
Thank you for your patience.
I Simply turn off Dynamic Laser Control , so set it to Off, and perform a usual step by step calibration.
I also use patterns without info letters (A letter at the corner).