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Hi,
After numerous attempts to create a good profile and eeColor LUT for my JVC X35 projecter I am at a loss. Ted at DisplayCalibrations.com has been a fantastic help in analyzing the LUTs and guiding me but he does not know DisplayCal. He says the LUTs don’t seem to be correcting red at all and the gamma is a disaster, up around 2.5, crushing the blacks. I have tried many different settings in lut creation and it doesn’t get any better.
I have attached the profiling log and the latest LUT log as a starting point. Any help at all would be greatly appreciated.
Andrew
Hi Florian,
Here is the file. I have excluded the actual LUTs. Thanks for taking the time to help.
Andrew
The projector seems to have slight brightness fluctuation in the lower (roughly) 20% of the grayscale – not too egregious. The really low Rec. 709 coverage of only about 82% is bad though, so it’s no surprise that all the primaries clip. Other than that, the 3D LUTs look fine. If you want to compress instead of clip, you can create a perceptual 3D LUT.
Thanks for the response. The primary issue is that I cannot seem to get the gamma down to a place that looks good. All the blacks are crushed no matter what settings I try when creating the LUTs. Also there is always a “Warning :- RGB black point hack didn’t trigger!” message when creating a LUT. Is this a problem?
Yes the projector gamut doesn’t cover rec 709 at the cyan to green end and the red is much larger. The issue is that the LUTs all still end up with too much red.
Do I need to re-profile with different settings or is the profiling fine and I can you suggest what I do to create a better LUT?
I have attached a pre and post LUT report if it helps.
Andrew
Thanks for the response. The primary issue is that I cannot seem to get the gamma down to a place that looks good.
That’s a surprise because none of the 3D LUTs does change the native gamma by much (except the perceptual appearance one and the one with output offset at 100%, which is expected).
there is always a “Warning :- RGB black point hack didn’t trigger!” message when creating a LUT. Is this a problem?
No.
the red is much larger.
The projector falls short significantly for all colors (except blue), look at the a*b* gamut graph.
Do I need to re-profile with different settings
Does the projector have a wide or native gamut mode?
I have attached a pre and post LUT report if it helps.
Not really unfortunately because it doesn’t say anywhere which of the 3D LUTs has been active. Also, it doesn’t tell the verification settings (Bt. 1886? Gamma 2.2? These need to match, exactly, the 3D LUT settings!)
Could there be a native gamma issue? Is the 1D LUT added into the 3D LUT not supposed to correct this and is that a possible profiling/correction problem? What can I do to deal with the crushed blacks? Is there setting I can try?
This is the wide Gamut mode of the projector. Perhaps a bulb issue? The Gamut in this proj does fall short in green but the reviews from years ago never showed that bad of a problem. Any suggestions?
Sorry about the report. It is from another software ;-( Is there anything else I can send?
Andrew
Could there be a native gamma issue?
No.
Is the 1D LUT added into the 3D LUT not supposed to correct this and is that a possible profiling/correction problem?
The 1D calibration has nothing to do with this. Also, for all the 3D LUT presets in DisplayCAL, calibration is linear (same is true in your case).
I notice you’re driving the projector in video levels in DisplayCAL. Normally I wouldn’t expect this to be necessary, because the graphics driver will do the 0..255 to 16..235 conversion unless you deliberately changed its output levels setting. Maybe this also explains the quite low (even for projection) contrast of only about
250:1550:1?I have matched the PC output to the OPPO DVD player output (primary video source) by matching Ted’s disc levels and the DisplayCal signal generator levels. The entire chain is at video levels. I have measured a much higher contrast level (using different software) and the contrast seems very good. 100% white is almost 50 cd/m2 and blacks are black. Is this not good?
Andrew
The measurements tell me your black is at around 0.0839 and white at 47 cd/m2. You should check if you have double conversion to video levels – if Windows itself does not look like it crushes blacks for its GUI elements, then you definitely need to use output levels 0..255 in DisplayCAL because the graphics driver is already handling the 0..255 to 16..235 conversion. Note that 3D LUT encoding still should be 16..235.
I would also generally recommend leaving the output levels setting at “Auto”.
Thanks Florian. I will try a few things and let you know what happens in a day or so.
Andrew
OK Step 1. I just verified white and black levels in DisplayCal.
Auto: White 54.6 cd/m2 – Black 0.01 cd/m2
TV RGB : White 45.6 cd/m2 – Black 0.08 cd/m2
I will re-profile in auto tomorrow and go from there.
Thank you Florian.
Andrew
HELP! Crash.
After 2 hours of measuring it crashed with the attached error message (see error.jpg) and then said profiling is not complete. I have also attached a zip of the created files in the temp DIR. Is it complete so I can go ahead and create some LUTs or do I have to re-profile?
Andrew
That’s not a crash. Seems like some other program has deleted the temporary files behind DisplayCAL’s back.
Actually the temp files were all there.
I believe the issue is the following:
- In the “Profile Name” field I added “WIDE ” to the end of the string.
- Unfortunately I added a space after the word.
- When Windows created the directory, it trimmed the trailing space (seems that this is standard).
- DisplayCal does not trim the trailing space, as you can see, all the filenames created have a space before the .extension.
- I believe that when DisplayCal attempted to copy the files from the temp directory to the directory it had created, it got stuck on the fact that a directory with the trailing space did not exist.
- All the files were still in the temp dir after the error message and I managed to save them.
Perhaps this trailing space in windows issue might be worth addressing in a future version. I am not sure how other OSs behave.
My question stands, given that I saved the files from the temp directory, did the profiling and calibration complete, or do I need to run it again?
Thanks,
Andrew
