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Shortly I will have access to a colormunki photo (spectro) and a colorhug2 (recent purchase), I’ll be creating a CCMX correction matrix for the colorhug to eliminate the uncertainty of using EDID-based CCMX (this is for a wide-gamut panel and I couldn’t find any reference CCMX out there for it; the EDID-based CCMX removed the red-tint of the colohug’s factory calibration).
I noticed that many advanced/knowledgeable users have both a spectrometer and a colorimeter – just to calibrate displays.
Question: why would people that have a colormunki (photo = spectro) still want a colorimeter? As I’ve read elsewhere – displaycal can perform calibration & profiling directly using the colormunki photo, so isn’t that better than using colorhug2+ccmx?
Sorry if this is a basic question – color profiling newbie here.
Calibrite ColorChecker Studio on Amazon
Disclosure: As an Amazon Associate I earn from qualifying purchases.I noticed that many advanced/knowledgeable users have both a spectrometer and a colorimeter – just to calibrate displays.
It’s because of the speed, most of the “low” cost spectrometers measure very slowly(especially on lower light levels). Pair that with long (but well worth it) time it takes to calibrate and profile properly and you can easily spend a lot of time.
Instead people use spectrometers to build corrections for their relatively fast colorimeters, and achieve good combination of accuracy and speed.
Instead people use spectrometers to build corrections for their relatively fast colorimeters, and achieve good combination of accuracy and speed.
In terms of accuracy (say I don’t mind some hours of desktop downtime while the calibration is done), is it reasonable to expect that the CMP spectro would produce a better profile than the CH2?
I’m trying to understand whether there is a gain in accuracy in addition to time by owning both devices. I know the CMP is a very old device but seems to be still respected, with known limitations; the CH2 has a modern sensor; do they somehow complement each other if the workflow is CMP/CH2 > CCMX > CH2 > .icc
I’m trying to understand whether there is a gain in accuracy in addition to time by owning both devices
Yes, there is. Spectrometers usually cannot measure as low as a good colorimeter when measuring darker colors, so apart from the speed difference, there can also be a precision and accuracy benefit (if the spectro is used to create a CCMX for the colorimeter, and this CCMX is then used with the colorimeter).
CCMX made with ColorMunki Photo uploaded to displaycal’s DB.
For reference,
Munki-based correction matrix:
BEGIN_DATA
1.246976 -0.0633189 0.000863733
0.0924945 0.909227 -0.00507435
-0.0393694 -0.0501627 0.953257
END_DATAEDID-based correction matrix
BEGIN_DATA
1.331150000 -0.087364600 -0.014811500
0.154284000 0.876884000 -0.000439381
-0.044976900 -0.032275400 0.965087000
END_DATAThe change (post-munki correction) is noticeable in the profile gamut surface/shape & volume but overall tonality didn’t change significantly. More of a refinement perhaps (to my newbie eye) even if the correction matrix shows some large changes of up to 80% in some figures.
AdobeRGB coverage shows a bitsmaller (97.8%, it showed as 99.8 with EDID CCMX, and 90% with CH2 factory calibration (and gave noticeable red shift))
Some peace of mind gained :), darktable photo editing shall start soon
Profiling using the colormunki-based CCMX and CH2 worked fine.
I wanted to also compare how calibration/profiling with colormunki alone would compare to the result I got from CH2+ccmx. So I tried to use displaycal to get this done – a few times: every time the process starts OK, I get prompted to calibrate the colormunki, then go through calibration, then profiling starts (ETA is about 2 hours, four times longer than with a colorimeter) and runs for at least half an hour, maybe more, but every time the process errors out before completing, with displaycall showing:
error new disprd failed with ‘instrument access failed’
After that, the colormunki is not usable (every operations fails immediately with this same error message) until I reboot the PC. Never had an issue with CH2.
This is with Fedora 24. I found many old reports about this same error and displaycal but no tips on how to fix this or address this. Is this a known problem of Linux+DisplayCal+ColorMunki? any tip or workaround?
See ticket #2057.
