Originally Posted by tn1krr
You are calibrating RS40 or RS50, right? I noticed similar thing (very very obvious color banding) with my X3 + Radiance XS when I tried to use "Wide1" color space and have the problem narrowed to 2 different options
1. Could be caused when X3 color saturation is brought down a LOT. Wide1 in X3 is very oversaturated so the colours are tweaked a lot when Wide1 is brought down to REC709. I have a wild theory that this somehow might cause banding due to color tracking issues or something with new JVC DLA
2. My Chroma 5. It seems to read quite considerably different than my Eye One pro. This has been collecting dust a bit too long so it may have to go to Spectracal for recalibration. Dunno if a bad meter could cause banding, not that experienced with this stuff yet.
I now have very nice calibration using Radiance, Calman 4.1 Enthusiast + E1 Pro but I had to use Standard color space where green is slightly undersaturated. But gamma/greyscale are tracking quite perfectly and everything is spot on on colours (best skin tones etc. I've ever seen with any projector) except very slight green undersaturation. CAnnot see the undersaturation on the screen, but knowing it is there pains me a bit. I'd actually propably want to create another CMS profile that is slightly and consistently oversaturated for cartoons etc.
I've been meaning to debug this a bit more (like trying bring wide1 to REC709 with Calman + E1P as I used C5 last I tried) before contacting Lumagen, but I've been super busy and doing a full calibration with E1 Pro a few hours every time. I try to watch a movie every now and then instead of always tweaking
The RS50 went back so I am am keeping the RS20.
I solved the problem. Had I done it more scientifically, I might have some insight about what is going on. As it is, I only have theories.
I had been calibrating the RS20 using the User1 Preset with the CMS turned off. This is probably the widest color space that the RS20 can muster. I changed this to the Cinema 2 preset. If I recall correctly, Cinema 2 is not as wide as User1 with the CMS turned off. Using Cinema 2, I now have no issues. This experience supports your theory that the largest color spaces are too wide to be brought in without banding. But, I don't think that the wide color space is the cause for me.
When I first began correcting my calibration, I measured what I had done earlier. For whatever reason, the Y of some of the colors was way too low - xy positions looked okay. So, I had added way
too much correction. I am still not completely sure why I did this but I have a theory. After I zeroed out my existing calibration and started from scratch, Everything was proceeding as it should. When I got to Yellow, I got some really weird readings. I was sure that they were not correct. So, I exited and restarted Calman. When I measured what I had done, R, G and B measured fine but C, M and Y did not. So, I was getting incorrect readings on these colors. I finished the calibration, correcting C, M and Y. Everything now measures correctly. I checked 100% stim and it is also fine.
I went back and looked at the material in which banding was obvious. It was gone. I checked for banding on cable and it was also gone.
So, I think the cause of my banding is that I added too much correction because I was getting bad readings. I am not sure why this happened. It could be that I was not diligent enough in reinitializing the i1pro over time and it was drifting. So I am thinking what happened to me is a measurement issue. The cause of it is probably me.
In your case, I would not accept an undersaturated green. If you saved your "Wide" Calibration, I would go back and remeasure it. Measure it with both the i1pro and the Chroma 5 and attempt to draw some conclusions. If it was truly accurate when you did the calibration, it should still be accurate now (but I always get slight measurement differences when I got back and remeasure).