Display Calibration

[chros]

Here are the results from tonight
But with which settings? :)

a 3d lut creates an image that looks right on your screen and only on your screen.
Screen shots don't show us anything, they look different on my screen than they do on your's. ;)
Yep! Another thing, calibration at the GPU messes up the colors if you are capturing the screen.
https://www.google.com/search?q=fraps+yellow+tint
It's true but it can show us mayor flaws like elevated shadows, etc.

[seiyafan]

Is 3d LUT same as .icc profile? My question is if I create a 3d LUT for MadVR, can I also use that profile on the same monitor for photo editing? Will all the colors look accurate for both movies and photos?

[Arm3nian]

I ended up returning the VP2780-4k. I wasn't happy with it. Cost $100 to ship it all the way to New York from Las Vegas but it's better than paying $700+ for something that doesn't impress you.

I ended up getting the PG279q. A lot of units have QC issues, but they seem to be getting better. Mine doesn't have anything serious, but it does have some uniformity issues. They're all over the monitor when you look for it on lets say a red background. The most noticeable is on a white background when on web pages, where the top 30% looks significantly more dim than the rest.

I don't think the PG279q comes factory calibrated, but after my i1 pro and dispcal calibration, the difference was obvious. A single windows calibration looked better than all the profiles and 3d luts I made with the previous display. The contrast is also really good, 1200+ after calibration, and blacks look nice for an IPS.

The gaming features are a little gimmicky imho. The display goes up to 165Hz, but it's hard to notice much difference after 120Hz, maybe even before it. ULMB pwm flicker just makes my head hurt after 5 min of use, and has ridiculous ghosting, making it unusable. Gsync is cool, but it's badly implemented on the software side. Blizzard games for examples don't work properly with it. For diablo 3, you need to enable vsync in game and turn off fps cap for it to work, which causes micro stuttering :confused:.
In WoW, the fps limiter in game is completely broken, and 3rd party doesn't work correctly with the engine. My 980ti can easily maintain 165fps in a specific area (and the game in general), but it drops to 128-153 randomly in the same exact area with the gpu at 65% load and the cpu at 23%. In more demanding games, you don't get a huge stutter, but I can still feel choppiness when it drops to 60's. That's the biggest problem with high refresh rate. After 165Hz, 60Hz is disgusting until your brain adjusts. 1440p is nice. I sit about about a foot away, and often can notice the pixels, where it was impossible to on 4k. But at least I don't have to deal with scaling issues.

I have until January 30th to return it. I should really focus more on my engineering coursework rather than games, so it'll probably be going back if I get free shipping.

Back on topic, I didn't use any of the fancy features in dispcal. I targeted a specific white level and white point to help me set it as desired, then went back and changed to as measured. The windows calibration looks great. From that, I made the 3D lut, and it looks good in movies. I'm guessing it is better to create a new profile for madVR and target Rec. 1866 instead of 2.2 gamma? It feels weird for the tone curve to be gamma 2.2, and then the 3D lut to be set to Rec. 709? Probably worth it to make the new profile.

[e-t172]

Is 3d LUT same as .icc profile? My question is if I create a 3d LUT for MadVR, can I also use that profile on the same monitor for photo editing? Will all the colors look accurate for both movies and photos?

A 3DLUT is not an ICC profile.

What ICC-aware applications (e.g. Photoshop) do is, they use the ICC profile that's set in the Windows color control panel applet to generate a 3DLUT on the fly and use that to display accurate colors. Non-ICC aware applications don't know how to do that and therefore don't use the ICC profile. However they are still subject to the 3x1DLUT calibration that's stored (vcgt) in the ICC profile which is applied to the entire output of the GPU, making things especially confusing.

Unfortunately, madVR is not ICC aware (I've tried to convince madshi to implement ICC, but to no avail (http://forum.doom9.org/showthread.php?p=1647449#post1647449)). However, it can load "raw" pre-generated 3DLUTs, so if you generate a 3DLUT from your ICC profile, you can achieve the same end result as an ICC-aware application. The only difference is that it has to be done manually - madVR is not smart enough to deduce the 3DLUT from the ICC profile set in the Windows options.

[huhn]

windowed overlay reads the ICC and ignores the gamma ramp by default. i don't know what it reads from it.

it's nice if you can read an ICC and use this but there is a good reason collink needs minutes or even up to hour to create a 3D LUT.

[seiyafan]

I see, so it looks like I need to calibrate my monitor twice, one for photo (2.2) and the other for madVR (Rec. 1866), because the .icc generated for Rec. 1866 would not work well for photos, I just need to get the 3D LUT file generated to be imported into madVR, and the .icc calibrated for 2.2 gamma would be loaded into Windows. Is this logic correct?

Another question, since my monitor is not wide gamut, should Rec. 709 be used instead of 1866? Excuse my n00bness, I am not good with the technical jargon.

[huhn]

for a 3D LUT only the readings matter.

so you can create a bt 709 profile from the start and use this to create a 3D LUT.

BT 1886 has the same gamut as bt 709 it's just a "different" gamma depending on the "black" your screen has.

[seiyafan]

I see, I have an EIZO IPS with 1000:1 contrast ratio, but nowhere near as black as any OLED. Is it still okay to go with BT 1886?

[e-t172]

it's nice if you can read an ICC and use this but there is a good reason collink needs minutes or even up to hour to create a 3D LUT.

3DLUTs can be cached. Also, how do you manage to make collink run for an hour? That's crazy. On my machine it usually runs in seconds. Are you using "high quality" (-q h) options despite the Argyll documentation explicitly telling you not to do that?

I see, so it looks like I need to calibrate my monitor twice, one for photo (2.2) and the other for madVR (Rec. 1866), because the .icc generated for Rec. 1866 would not work well for photos, I just need to get the 3D LUT file generated to be imported into madVR, and the .icc calibrated for 2.2 gamma would be loaded into Windows. Is this logic correct?

Technically, you can calibrate your monitor to anything you want; anything you do will be compensated back when you generate a 3DLUT, or when your photo software reads the monitor's ICC profile. Calibration is just a way to get the monitor to behave nicely with applications that are not ICC-aware; what matters for madVR or ICC-aware software is correct monitor characterization (i.e. profiling).

Technically, calibrating as close as possible to the actual colorspace of your content might increase accuracy and reduce banding, but by how much is up for debate.

Another question, since my monitor is not wide gamut, should Rec. 709 be used instead of 1866? Excuse my n00bness, I am not good with the technical jargon.

Rec. 1866 is not a gamut, it's a gamma curve. Rec.709 is a gamut. Using Rec. 1886 "instead of" Rec. 709 makes no sense, because they are complementary. You use Rec. 1886 with Rec. 709.

I see, I have an EIZO IPS with 1000:1 contrast ratio, but nowhere near as black as any OLED. Is it still okay to go with BT 1886?

Yes. In fact, that's one of the reasons why BT.1886 was introduced in the first place (i.e. achieve correct results in displays with imperfect black).

[huhn]

3DLUTs can be cached. Also, how do you manage to make collink run for an hour? That's crazy. On my machine it usually runs in seconds. Are you using "high quality" (-q h) options despite the Argyll documentation explicitly telling you not to do that?

default dispcal gui settings take about 4-5 min.

-r 256 can take a lot longer time easily an hour. if this is like -qu than don't use it but there is no word about not using high.

[seiyafan]

Heh, so much to learn. Last question for now, under Video 3D LUT for madVR, the default tone curve is 1886 with 2.4 gamma (as opposed to 2.2), and rendering intent is set to "Absolute colorimetric with white point scaling" is because these are recognized to be the better settings for movies after extensive testing right?

[huhn]

yes. BT 1886 is currently the correct "SPEC".

on a screen with perfect black (OLED) it is gamma 2.4.

[seiyafan]

For non-perfect black monitors should gamma 2.2 be used instead? Or stick with 2.4?

[huhn]

no BT 1886 it does the rest by it self that's why we have it now.

in the end gamma depends on your ambient light. this is for bat-caves.

in a day light flooded room you are not going to like a gamma of 2.4

[seiyafan]

I see, since most people watch movies in a darker room 2.4 is preferred over 2.2

[huhn]

yes before BT 1886 a gamma of 2.4 was correct.

[seiyafan]

Correct me if I am wrong: If I want to use gamma 2.2 for general application (Web, photos, etc.) and Rec. 1866 for movies. I would run calibration twice, first time with gamma 2.2 to create an ICC file for Windows (run "dispcalGUI profile loader" at startup), second time with gamma Rec. 1866 just for creating a 3D LUT file for madVR. Is this the right flow?

[huhn]

you can just calibrate for 2.2 and create a 3 d lut from it.

[seiyafan]

I see. The reason I am asking is because I have been reading this guide:
https://imouto.my/tutorials/madvr/#3dlut
and in step 7, it selects Rec. 1886 as opposed to 2.2, I wonder if there is a specific reason for that.

[Asmodian]

When creating the 3DLUT you can set a BT.1886 gamma as the target even when you have used a 2.2 gamma for normal calibration. I have not noticed any downsides when doing this.

That guide recommends a BT.1886 gamma curve for calibration (as do I) but if you want a pure power 2.2 instead go for it. :)

[seiyafan]

Got it working, thanx!

[seiyafan]

I took screenshots for different calibrations. Could you please provide some comments from the comparisons below, I don't know how to tell which is good or bad.

http://screenshotcomparison.com/comparison/155196

http://screenshotcomparison.com/comparison/155197

It seems with 3D LUT pictures become warmer with a reddish tint. I don't know if that's what it supposed to be or not.

[foxyshadis]

I took screenshots for different calibrations. Could you please provide some comments from the comparisons below, I don't know how to tell which is good or bad.

http://screenshotcomparison.com/comparison/155196

http://screenshotcomparison.com/comparison/155197

It seems with 3D LUT pictures become warmer with a reddish tint. I don't know if that's what it supposed to be or not.

When you label it "3D LUT 1886 (gamma 2.4)" is it BT.1886 or gamma 2.4? They're very different in the shadows and midtones, even if highlights are similar; BT.1886 is much closer to 2.2 than 2.4.

[seiyafan]

When you label it "3D LUT 1886 (gamma 2.4)" is it BT.1886 or gamma 2.4? They're very different in the shadows and midtones, even if highlights are similar; BT.1886 is much closer to 2.2 than 2.4.

Please see the pic below:

On a separate note: I bought the i1Display Pro more than 3 years ago. Has there been any released firmware for it? Because I couldn't find any on their official website.

[huhn]

When you label it "3D LUT 1886 (gamma 2.4)" is it BT.1886 or gamma 2.4? They're very different in the shadows and midtones, even if highlights are similar; BT.1886 is much closer to 2.2 than 2.4.
bt 1886 can be very close to gamma 2.2 if the black point of the screen is bad. but i can be gamma 2.4 too if the black is perfect.

so judging bt 1886 doesn't work without the screen.

@seiyafan

it's impossible to judge a 3d lut for your screen without a lot of guessing.

so make sure you used the correct correction and check the calibration.

you can do this using "tools -> verify calibrations" in dispcal gui.

have you calibrated the white point before you created the 3d lut?

[seiyafan]

Thanks for your suggestion. I used "as measured" for white point when I created the 3d lut, I will also check the verification later.

[Nullack]

Has anyone got any source for test patterns including pluge at 4K in RGB PC levels? Everything Ive found is TV levels calibrated.

[huhn]

limited range and full range has nothing to do with how you calibrate.
same for resolution.

[Nullack]

Well you seem to be the only one saying that. Everywhere else I look, is pluge patterns to say 16D blackness and then ones specifically different coded to RGB where zero is the black with no blacker than black unlike the 16D TV style levels ones. Please explain.

[chros]

Everywhere else I look,
For example?

[huhn]

Well you seem to be the only one saying that. Everywhere else I look, is pluge patterns to say 16D blackness and then ones specifically different coded to RGB where zero is the black with no blacker than black unlike the 16D TV style levels ones. Please explain.

a limited range source is rendered at full range so i can't follow you.

[foxyshadis]

Nullack, how many times do you have to be told to ignore old Studio RGB standards? Every video codec/renderer decodes to 0-255 RGB, your monitor displays 0-255 RGB, that's all that should matter. 16D isn't even a real term.

[Nullack]

The simple fact is, not everyone agrees with Foxyshadis. I would hope you to have the maturity to accept that your own theories may not be shared universally by all. Many people particularly on the consumer electronics side consider TV level calibrations to be the right way to go on any TV, including digital ones being fed digital signals from a HTPC.

However foxyshadis if you bothered to actually read my post, you would see *Im trying to do PC level* calibrations. Even a most cursory look at my post would have given you that. Instead of going off on an unrelated point, how about addressing what I actually said, which is about finding PC level 4K calibration test patterns.....

[huhn]

sorry the issue here is that you don't understand calibration

[Nullack]

.
same for resolution.

So you have invented a perfect scaler then and can miraculously do test patterns like sharpness in an optimal way even when you have to scale the test patterns to have it display at native resolution :eek:

[Nullack]

sorry the issue here is that you don't understand calibration

If you believe that, explain precisely where you think Im wrong. I do believe I do understand it.

[huhn]

So you have invented a perfect scaler then and can miraculously do test patterns like sharpness in an optimal way even when you have to scale the test patterns to have it display at native resolution :eek:

black boarders?

[Nullack]

Huhn I know you have allot of video knowledge and I'm thankful for insights you have offered in the past :) In this case though, I really dont think you get whats driving what Im asking and sometimes I get the impression english isnt your common language. Ill try to explain. The thing about test patterns is they need to be "reference quality". They need to be verified they are correct - for example the ISF have a process for this and they explained it when they published some ISF test patterns. As you know there is allot of different test patterns that do different things. The reason I want 4K test patterns in particular is to send *native" resolution images to the *native* resolution of the display so as to avoid any non reference artifacts in the image. I gave the example of sharpness tests. Those sorts of test patterns are useful in native resolution because of how fine the detail gets with testing sharpness. As you'd know, 4K is allot more pixels than full HD. The value seems obvious to me in these sorts of cases to be able to do native resolution test patterns.

Im not arrogant and I do listen to contrary arguments that are rational. If indeed your convinced I'm wrong about this topic, then please explain why you think so. Just saying that I dont know doesnt contribute anything of substance to the discussion.

[huhn]

like I already said levels doesn't matter if you 100% know how they work.

that's mean you know the render/desktop side, the GPU side and the TV side of "levels".

just a small example. if you set the GPU to YCbCr or limited range RGB than you will not get information in the WTW and BTB parts no matter what.

if you take a 1080p test image and want to use it at an UHD screen than you use black boarders for that (zoom 100 %). the image in the middle is still bit perfect.

works with http://www.lagom.nl/lcd-test/white.php
and works with these test pattern: http://www.avsforum.com/forum/139-display-calibration/948496-avs-hd-709-blu-ray-mp4-calibration.html

[Nullack]

if you take a 1080p test image and want to use it at an UHD screen than you use black boarders for that (zoom 100 %). the image in the middle is still bit perfect.

Ok I see. Just dont scale it when using test patterns lower than the native resolution. While I realise that would work, I would prefer to deal with things like sharpness at full screen so I can carefully try to tune into the reference standard. Thanks

[huhn]

NN x2 scaling should work for most test patterns too.

a good sharpness test picture works like this: http://www.lagom.nl/lcd-test/sharpness.php

so a smaller picture helps a lot to do this test.
this test for example isn't affected really by NN x2 scaling.

[chros]

So, I have finished playing with profiling, so I try to summarize what I understood so far. And thank all of you for the great help.
If you need the black point hack you almost always get crushed shadows.
Probably that's right if you use dispcal.exe at the first step (see below for alternative way), at least it worked like this on my setup.
About the black crush: I noticed that the cause of it is the "-G2.4 -f0 -k0" switches in the dispcal command. If I leave it out and '-b' switch is also present I won't get black crush.
b) with dispalGUI the situation is pretty interesting, it uses different method: setting measured (as target) everywhere (the full log is here: http://pastebin.com/nPrEspS1 )
here are the commands (timecodes are included):
00:39:30,080 dispread.exe -F "-P0.5,0.5,9.486833" -v -dmadvr -c1 -yn -X CCFLFamily_07Feb11.ccss -K "madVR 2015-12-06 00-38 S XYZLUT.cal" "madVR 2015-12-06 00-38 S XYZLUT"
00:42:46,055 colprof.exe -v -qm -ax -bn "madVR 2015-12-06 00-38 S XYZLUT"
And that's pretty interesting indeed, if you leave the tone curve setting at 'measured' on Calibration tab in dispcalGUI then it won't use dispcal.exe at the first step but instead:
- it will use dispread.exe with predefined (!) .cal (calibration) and ti1 (testchart with 154 patches) to create a measured .ti3 file
- then colprof.exe will provide the necessary .icm file from the above .ti3 file to be able to use targen.exe in the next step
As I reported, I don't have any problems with this method. So I went for this.

(-i switch) Asmodian used -ims , dispalGUI offers -iaw by default. The difference is the -ims is relative, while -iaw is absolute. They state that -iaw supposed to be more accurate (I didn't had the time to test it on my setup though).
So, I tried out all of them: only the types that belong to the absolute group produced acceptable results and I couldn't really see the difference between them. For example -ims , -is switches produced oversaturated colors that was so visible as well. So I settled down with the -iaw switch (Absolute with white point scaling).

In fact, that's one of the reasons why BT.1886 was introduced in the first place (i.e. achieve correct results in displays with imperfect black).
I wonder what implications -IB:x.x:2.4 switch or output offset slider has for stuff level adjustments etc. I assume defaults are the most accurate ...
yes. BT 1886 is currently the correct "SPEC".
no BT 1886 it does the rest by it self that's why we have it now.
I would argue about this. This is the reason why:

in the end gamma depends on your ambient light. this is for bat-caves.
in a day light flooded room you are not going to like a gamma of 2.4
so judging bt 1886 doesn't work without the screen.
These are the most important facts.

I targeted a specific white level and white point to help me set it as desired, then went back and changed to as measured. The windows calibration looks great. From that, I made the 3D lut, and it looks good in movies. I'm guessing it is better to create a new profile for madVR and target Rec. 1866 instead of 2.2 gamma? It feels weird for the tone curve to be gamma 2.2, and then the 3D lut to be set to Rec. 709?
I see, I have an EIZO IPS with 1000:1 contrast ratio, but nowhere near as black as any OLED. Is it still okay to go with BT 1886?
I wonder what implications -IB:x.x:2.4 switch or output offset slider has for stuff level adjustments etc. I assume defaults are the most accurate but I too have found the shadows to be somewhat lifted on my IPS panels so I'm tempted to try reducing that now.
If someone hasn't seen it yet, I made a post about gamma here: http://www.avsforum.com/forum/139-display-calibration/1471169-madvr-argyllcms-139.html#post40108362

[Arm3nian]

Is it possible to get non oversaturated colors on a high gamut display using dispcal and a color managed program?
For example, if I choose sRGB tone curve, and create an icc profile and import it in firefox, will colors look normal?

I still need a monitor (returned the pg279q lol). 4k bluray is coming in less than a month and is has a larger color space and is 10bit. The new dell ultrasharp's have ~98% dci-p3 and are cheap ($700) for the supposed quality you get; gb-led, 10bit, 1440p etc. They currently seem like a good purchase.

What about madVR? Do you need a 3Dlut for proper color space conversions, i.e rec. 2020 to .709? What about 4k bluray on a display that has high dci-p3 coverage, works by default?

[Siso]

Is madvr yCMS calibration option useful for sRGB monitors?

[Asmodian]

Is it possible to get non oversaturated colors on a high gamut display using dispcal and a color managed program?
For example, if I choose sRGB tone curve, and create an icc profile and import it in firefox, will colors look normal?

I still need a monitor (returned the pg279q lol). 4k bluray is coming in less than a month and is has a larger color space and is 10bit. The new dell ultrasharp's have ~98% dci-p3 and are cheap ($700) for the supposed quality you get; gb-led, 10bit, 1440p etc. They currently seem like a good purchase.

What about madVR? Do you need a 3Dlut for proper color space conversions, i.e rec. 2020 to .709? What about 4k bluray on a display that has high dci-p3 coverage, works by default?

Yes, it is possible to get non oversaturated color on a high gamut display as you stated. A lot of applications that use ICC profiles only use the simple 1DLUTs (gamma ramps) for calibration which does not correct the gamut but Firefox, Chrome, Photoshop, etc. will.

For madVR you only need a 3DLUT if you want to use your display's true gamut but if your display's native gamut is close to one of the options in "this display is already calibrated" madVR does the proper conversion from the source gamut to the display's gamut.

Options available:
BT.709
SMPTE C
EBU/PAL
BT.2020
DCI-P3

The one important option missing is AdobeRGB but for those new ultrasharps DCI-P3 would probably work pretty well. :)

The biggest issue I have with any wide gamut display is streaming video, I have never found a method to correct streaming video. :(

Is madvr yCMS calibration option useful for sRGB monitors?

Not really IMO, only if you aren't really very close to sRGB.

[Siso]

Yes, it is possible to get non oversaturated color on a high gamut display as you stated. A lot of applications that use ICC profiles only use the simple 1DLUTs (gamma ramps) for calibration which does not correct the gamut but Firefox, Chrome, Photoshop, etc. will.

For madVR you only need a 3DLUT if you want to use your display's true gamut but if your display's native gamut is close to one of the options in "this display is already calibrated" madVR does the proper conversion from the source gamut to the display's gamut.

Options available:
BT.709
SMPTE C
EBU/PAL
BT.2020
DCI-P3

The one important option missing is AdobeRGB but for those new ultrasharps DCI-P3 would probably work pretty well. :)

The biggest issue I have with any wide gamut display is streaming video, I have never found a method to correct streaming video. :(



Not really IMO, only if you aren't really very close to sRGB.

I see, thank you for the answer, I'll stick with 3DLUT :)

[Arm3nian]

Yes, it is possible to get non oversaturated color on a high gamut display as you stated. A lot of applications that use ICC profiles only use the simple 1DLUTs (gamma ramps) for calibration which does not correct the gamut but Firefox, Chrome, Photoshop, etc. will.

For madVR you only need a 3DLUT if you want to use your display's true gamut but if your display's native gamut is close to one of the options in "this display is already calibrated" madVR does the proper conversion from the source gamut to the display's gamut.

Options available:
BT.709
SMPTE C
EBU/PAL
BT.2020
DCI-P3

The one important option missing is AdobeRGB but for those new ultrasharps DCI-P3 would probably work pretty well. :)

The biggest issue I have with any wide gamut display is streaming video, I have never found a method to correct streaming video. :(
I see... Why doesn't windows have proper color management by now:mad:

So unless your monitor is in Photoshop 24/7, there really isn't a point in wide gamut. I guess you could get accurate colors on the web, but content is basically all sRGB, so you're just wasting money. With UHD and madVR you could benefit, but a higher contrast ratio is probably more important than a larger color space, which rules ips panels out for viewing, as opposed to creating.

[Asmodian]

I see... Why doesn't windows have proper color management by now:mad:

So unless your monitor is in Photoshop 24/7, there really isn't a point in wide gamut.

I agree that it is very annoying that Windows still lacks the ability to do gamut conversion.

I would even go so far as to say that there are large negatives to a wide gamut display unless your monitor is in Photoshop 24/7. :mad:

A DCI-P3 OLED for movie watching with madVR would still be quite enticing, assuming I could get any content in wide gamuts. :p

[Arm3nian]

I got my UP2716d today (ordered it before our discussion on wide gamut).

The first thing that came to mind was wow, vibrant colors, not over saturated and bad looking. It looks a bit like a samsung phone, which imo looks the best out of all phones screens. This is the best looking display I've seen, and it's not like I paid 2,000 for it, only $700, which is less than my previous monitors. It comes default in adobeRGB color space. sRGB looks very faded, I wouldn't use it, unless I calibrate it. But I don't think I need to use it, because adobeRGB looks excellent. DCI-P3 mode has very nice colors, but it's dim (obviously for movies), but I don't have any content in DCI-P3 yet. UHD movies come in less than a month I think. I have not calibrated it yet, but ran a color test chart in dispcal and I see colors I've never seen before. They don't look incorrect.

I can select 10bpc in NVCP with my 980ti. Do you know how to use madTPG for normal calibrations, or is it not good to do that. IIRC madTPG has 10bit output?

[Arm3nian]

I've found something a bit weird. The monitor on default is in "standard" mode. Everything looks great, and dispcal shows 100%sRGB and 99.7% adobe RGB and 93% dci-p3. When I switch from standard mode to color space, and select adobe RGB, reds turn orange... sRGB emulation mode also looks makes reds look orange. wtf lol