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Hi Florian,
I feel like I am pestering you but I’ve got to overcome this somehow!
As you noticed, I have been playing with calibrations recently – overcome the metamerism issue, brightness issues etc.
Now I have realised that my blacks are crushed. I had that feeling by watching a movie and a quick test confirmed that. I used BT.1886 2.4 Absolute as gamma curve. I appreciate the black level of my Panasonic is not great but I thought the 1886 would take that into account.
So yesterday I ran several calibrations only (to save time) using Windows and not MadVR – again, to experiment with different settings without having to wait too much for the 3DLUT to complete. I also set the calibration speed to “very high”
I tried different settings of 1886 (1.8, 2.0 and 2.4) and also Gamma 2.2 set to 1.8 and 2.2. I also tried setting the black output offset to 100% when using 1886.
In the end I obtained a decent result by setting 1886 2.0 set to relative. Level 17 is still not visible but we’ve discussed that before and I can overcome that by setting a ‘custom’ level on madvr of 1-255.
So I ran the calibration and profiling again – this time using MadVR and calibration speed set to “high”. I set the 3DLUT page to the same gamma setup (1886 – 2.0 – relative) and ran it.
I ended up with a slightly improved but still not acceptable – from my perspective – black behaviour. The attached are what I got by calibrating Windows and madVR to the same parameters.
I have calibrated my main DELL monitor using a ‘standard’ 1886-2.4-absolute using madvr and 3DLUT and the black details in the scene I used for comparison are MUCH higher.
Just so you know:
- The room is not completely blackened by most of it. Screen wall is black, ceiling is dark blue and walls have dark blue patterns on them.
- IRIS is disabled when calibrating
- No stray lights in the room
- I did not take a picture but when running 1886 2.4 Absolute I cannot see any of the bars flasing on the black levels test. I have to raise the brightness by at least 10 in order to see something flashing on the 25 level.
- The HDMI level is correct. In fact, I had recently switched to limited (16-235) but then moved back to full (0-255) after reading that madshi is strongly recommending that.
I am attaching two actual pictures to show you what’s happening. Again, I appreciate my probe is not totally accurate at low levels and the projector black level is quite high, but I do not understand why the software is unable to set the low levels correctly.
I have to mention that when the calibration goes through the last step – the darkest – I usually hear the “beeps” (when the software is trying different settings and it’s still not happy with the outcome) but on screen there is absolutely no colour/brightness changes whatsoever – totally black (well, projector black).
Any help is appreciated, again.
Thanks
Tony
This very much looks like your levels are not set up correctly (either in madVR, or any other component in the chain, and there are many when it comes to video playback), especially since the Windows calibration result looks fine.
Ok, thanks.
Places I know are:
- Video card (nvidia control panel which is currently overridden to 0-255)
- MadVR (set to 0-255)
- Projector (HDMI level which is set to “extended” and brightness which is set to zero).
Yes, I can achieve a decent result by not using madvr but ONLY when using 1886, 2.0 and Relative. I would be happy to tweak the levels a little via projector or madVR but not by 50 points – that introduces artefacts. But I’ll try what you are saying, it makes sense.
the 3DLUT section has an input level section: is that correct when set to 16-235? I guess that is referring to the content and not the output?
Am I correct in setting the 3DLUT to the same setting (1886 – 2.0 – relative) used under “profile”?
Cheers.
the 3DLUT section has an input level section: is that correct when set to 16-235? I guess that is referring to the content and not the output?
For a madVR 3D LUT, 16-235 is always correct (irrespective of output level setting in madVR), and yes, for madVR that relates to the content.
Am I correct in setting the 3DLUT to the same setting (1886 – 2.0 – relative) used under “profile”?
I assume you mean under “Calibration”.
Am I correct in setting the 3DLUT to the same setting (1886 – 2.0 – relative) used under “profile”?
I assume you mean under “Calibration”.
No, I mean under 3DLUT settings – see attached.
I’m trying again now. Indeed the brightness level on the projector was 5 points off.
An update.
First, I reckon the answer to my question above is “no” as the 3DLUT settings refer to the content and not the display – am I correct?
Second, the new 3DLUT is still showing crushed blacks despite improved native black level. In fact, it is worsening the native response of the projector. I must have ran 50 calibrations over the past weeks, please could you have a look at what I am doing wrong? I am a persistent man but this is getting frustrating!
Cheers
I don’t think you have to run new calibrations each time. Just build a new 3D LUT from the existing profile and try different rendering intents and see how that impacts things.
Ok, I thought the whole calibration process was to be re-done.
It is clear now that using Windows I can have proper results – as expected. I am currently running madVR without a 3DLUT and a 1886-2.4-absolute is providing the result I would expect.
What I can’t have working well is the 3DLUT. Would you expect this kind of behaviour? I will try all the different rendering intents as you suggest.
It is clear now that using Windows I can have proper results – as expected.
Note though that this doesn’t correct the gamut as the calibration via the video card gamma table is 1D.
That’s why I ended up with an HTPC for my setup and I am trying so hard to get a 3DLUT to work! It does work on my monitor though, there must be something with either the not-so-good projector or the high black level or <dunno>.
Proper blacks are more important than proper colours to be honest, that’s why I am using a 1D correction for the time being.
I’ll keep trying but if you have any further input it’s welcome as usual.
Thx
Would a different gamma curve solve the crushed blacks? I used Displaycal to calibrate my Asus PG279Q and build a 3DLUT for Reshade and I had to use sRGB instead of Standard 2.2 or it’s quite literally lights out while gaming. Google was incredibly sparse on the subject.
As an aside, this is an amazing program and thank you to its creator(s).
The gamma should not affect the black level. Did you check your black level using a chart?
i did try several values though. What’s the difference between gamma 2.2 and sRGB?
