Projector Reviews

Optoma UHD51A A Smart 4K UHD Projector Review – Advanced Calibration

Optoma UHD51A A Smart 4K UHD Projector Review – Advanced Calibration: CMS Calibration, Calibration Charts

CMS Settings for Best (dark room) calibration – Reference Mode

RGBCMY Hue Saturation Gain
Red 6 0 0
Green -8 -1 0
Blue -4 -3 -2
Cyan -10 0 -3
Magenta 0 -5 0
Yellow 7 -1 -10

Color performance (based on measurements) was a little disappointing and using the projectors CMS (color management control) did little to help things. It didn’t seem to make any real difference which color gamut preset I choose as they were all similar I ended up using the HDTV preset. Our target is REC.709 and while all 6 colors were able to hit there 100% saturation targets, it’s the lower in-between levels (i.e 80% 60% 40% etc) that had some issues with being over saturated. If I tried to lower those mid-level saturation points it would also lower the 100% saturation points reducing the REC.709 color gamut, something we don’t want to do. Now to be fair I have seen this issue with many other DLP projectors. Also, Green has an issue going towards yellow at 100% saturation and yellow going towards red causing 100% yellow saturation looking more golden in hue.

CMS Settings for Brightest calibration – User Mode

RGBCMY Hue Saturation Gain
Red 0 -2 10
Green -25 1 6
Blue 0 -3 6
Cyan -40 -3 10
Magenta 0 -3 4
Yellow 20 0 0

CMS for my Brightest calibration was similar to my Best/Dark Room calibration. I started with Cinema color gamut preset. As mentioned above, Cinema is very similar to HDTV with the mid and lower levels being over saturated. Because I have Brilliant Color set to 10, I increased the gain (luminance) of all the colors except yellow to help match the increased output of white.

CMS Settings for 4K HDR – HDR Mode

RGBCMY Hue Saturation Gain
Red 0 -1 0
Green 0 -1 0
Blue 0 -4 0
Cyan 0 0 30
Magenta 19 -2 0
Yellow -4 8 21

Quote from Optoma’s marketing material concerning the UHD51A’s color gamut: HDR signals are mapped using REC.2020 tone mapping and provides coverage for REC.709, DCI-P3 and a wide coverage color gamut”. I tried all of the gamma presets (native, cinema, HDTV & presentation) and all of them were quite similar to each other just like with 1080/SDR. I had already used HDTV & Cinema for my Dark and Brightest room calibrations so I choose Presentation for 4K/HDR.

Take a look at my post HDR Mode saturation sweeps and you can see that blue is the only color that makes it out to P3 with magenta getting close, all of the other colors especially green fall short by a bit. Calibration helped a tiny bit, mostly but mostly with hue errors.