Originally Posted by thrang
I had tried calibrating with the iris on manual a few times as well, but did not get as good results. However, the sensor was closer than my final attempt for the evening, and the iris was set at 75.
So I can try again at the further distance and a lower manual iris.
Are you suggesting doing the gamma first with manual iris, then greyscale and cms afterward with DI on? Or everything with DI off?
I'll also do an off the screen measurement as the Duo bug apparently is only affecting off the lens readings.
Yes, as some other posters already mentioned, I would calibrate EVERYTHING with DI=OFF... especially gamma/grayscale.
The reason being that GAMMA is defined as the curve of the various light output level (between 0%-100%) WITHIN a FRAME. Therefore, when you paused your movie, GAMMA is the relationship between the black and white (and everything in between) and how bright/dim they are with respect to each other, again, within that particular FRAME/scene. Notice that with that FRAME, the IRIS opening will be constant. The DI only have effect when you change to a different FRAME or scene...
Now, consider when you have DI ON and during calibration on grayscale.. when you project a 10% test pattern, the DI detect that it is not that bright, so it will close the IRIS down more to give you better black. When you project say a 70% WHITE test pattern, the IRIS will open up as it should be brighter.
If you calibrate your projector with those different IRIS setting, then you are not calibrating a single "FRAME", because the IRIS opening is different. You are probably calibrating 10 different "moving" frames and they probably do not have any relationship with each other... as the base 0% and 100% changes for each IRIS setting.
Hope this help. I know it sounds confusing, but hopefully if you read it a few times, you will understand.