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Author Topic: Colorchecker ICC camera profiles  (Read 2505 times)

Rado

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Colorchecker ICC camera profiles
« on: January 08, 2019, 01:03:32 PM »

I haven't tested it yet but it seems like the color checker software can now create camera profiles for CO

https://xritephoto.com/CameraICC
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digitaldog

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Re: Colorchecker ICC camera profiles
« Reply #1 on: January 08, 2019, 01:33:21 PM »

The question is, exclusive to Capture1?
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Andrew Rodney
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Doug Peterson

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Re: Colorchecker ICC camera profiles
« Reply #2 on: January 08, 2019, 01:46:30 PM »

The question is, exclusive to Capture1?

Capture One uses industry-standard ICC profiles.

Any software used to create ICC profiles can be used with C1 and any other program that supports industry-standard ICC profiles.

digitaldog

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Re: Colorchecker ICC camera profiles
« Reply #3 on: January 08, 2019, 01:58:46 PM »

Capture One uses industry-standard ICC profiles.

Any software used to create ICC profiles can be used with C1 and any other program that supports industry-standard ICC profiles.
I'm aware of the first point. And the 2nd. My question still remains unanswered.
I'll ping Xrite.  ;)
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Andrew Rodney
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FranciscoDisilvestro

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Re: Colorchecker ICC camera profiles
« Reply #4 on: January 08, 2019, 05:39:21 PM »

According to Anders Torger and the documentation for Lumariver Profile Designer, C1 has a special way to handle the tone curve, where a part of it is contained in the ICC profile. According to this, a custom profile optimised for C1 is not necessarily a "Universal" profile.

You can read about it here:

C1 profile curves

It would be interesting to know how the profiles from Lumariver Profile designer compara to those from the new X-Rite Tool

Dave Rosser

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Re: Colorchecker ICC camera profiles
« Reply #5 on: January 09, 2019, 11:53:04 AM »

I haven't tested it yet but it seems like the color checker software can now create camera profiles for CO

https://xritephoto.com/CameraICC
The PDF that comes with the software refers to how to create profiles for capture one and how to prepare the original shot of color checker in Capture One for use in the the tool, it also has instructions on how to use the resulting ICC profile.
My first try is shown in pictures below, D700sun.jpg is with a color profile generated using the tool, D700Sun1.jpg is with the default CO D700 profile.  The most noticeable difference is in the dark blue patch, which is very similar to dng profiles created using the software with Lightroom.

Dave Rosser

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Re: Colorchecker ICC camera profiles
« Reply #6 on: January 09, 2019, 01:02:27 PM »

Futher to my last post here are 2 pictures only differing in that one has color profile generated by the Colorchecker software (the one ending CC2.jpg) and 0ne is the Capture One default (ending CO3.jpg).  All other settings including color balance the same.

torger

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Re: Colorchecker ICC camera profiles
« Reply #7 on: January 10, 2019, 03:01:11 AM »

I haven't tested X-Rite's software, just looked at the video how it works, and looked at the train images above to make an A/B comparison.

As usual X-Rite software focus on ease of use which is a good thing for casual users, but in doing so they miss out a little on Capture One curve handling and possibilities to tune your general-purpose profile to taste. It seems like they really mean to use it for reproduction rather than general-purpose photography. For general-purpose I think it's better to have a more elaborate and configurable way to generate the profiles as you will generate profiles seldom and use it many times in many conditions.

Capture One profiles (or in any other raw converter for that matter) should be optimized for the curve you will use it with most, which for general-purpose photography is not the linear curve. That's why you export both linear and film curve when making a profile with Lumariver Profile Designer, one to get colorimetric data, the other to get the curve that will be used so the tone reproduction operator will work on the proper curve and optimize the tone reproduction for that. Another aspect is that Capture One expects some contrast to be stored in the ICC profile too, that's why Lumariver Profile Designer allows import of the bundled profile to extract curve from there, or you can design your own.

As you can see on the comparison shots the contrast of the X-Rite profile is lower as it doesn't take that into account.

When rendering a profile for linear curve and then using it with the film curve it will sort of work, thanks to that Capture One's working space RGB primaries are chosen well to minimize color shifts plus that the film curves lack shadow dip (further minimizes shifts). The shadow dip is supposed to be in the ICC profile itself though. So I wouldn't say it's a high-end way of making general-purpose profiles, and it's not how the Capture One bundled profiles are made either. They're not made for linear reproduction with a curve slapped on, they are made specifically to be used with the film curve, and then instead work a little bit worse with the linear curve, but that is how you want a general-purpose profile to be. For their digital backs Phase One have bundled separate reproduction profiles by the way.

Another aspect to look into, which is not evident from the train images, is how the profile makes gamut compression and roll-off bright colors to clipping. Capture One (or really virtually all raw converters) expects the general-purpose profiles to have some gamut compression built-in, and I'm not sure X-Rite is doing that or not from these images. If you make a reproduction profile you don't want any gamut compression at all of course, so I'm guessing they don't do any.

Otherwise one can see that Capture One bundled renders warmer hues compared to X-Rite. This is because X-Rite is more correct on the hues, Capture One's bundled look is generally quite yellow, which you may or may not like. Personally I prefer more neutral rendering than Capture One's bundled profile, but I tend still to manually tune the residual errors so they go towards warm especially on the reds and blues. Deep blue is difficult by the way, if you keep that reproduction accurate it becomes very dark, so almost all general-purpose profiles lighten it considerably for better although slightly less accurate tone reproduction on screen and in print. Many of those little aspects are taken into account when making a good general-purpose profile. General-purpose profiles are weakly output-referred (ie they take into account that they will be displayed and printed, but are not strictly locked to a specific color space), while reproduction profiles are colorimetric scene referred to be able to copy artwork and similar. These are quite different.

To summarize, it seems to me that X-Rite's profile maker is best suited for casual reproduction workflows, while not ideally suited for making general-purpose profiles.

(Unfortunately Capture One v12 has currently a bug in the transfer function export so profile making doesn't work with that version yet, I guess X-Rite's software is affected too, so one have to use v11, the resulting profiles can still be used in v12 though)
« Last Edit: January 10, 2019, 03:53:18 AM by torger »
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torger

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Re: Colorchecker ICC camera profiles
« Reply #8 on: January 10, 2019, 04:05:05 AM »

Capture One uses industry-standard ICC profiles.

Any software used to create ICC profiles can be used with C1 and any other program that supports industry-standard ICC profiles.

The thing with ICC profiles in raw converters is that while the format itself is standard, raw converter color pipelines and where the ICC profile are applied within them is not. So to make an ICC profile that really works in concert with the ICC-using raw converter you must know how it actually uses the ICC profile. For example a profile maker that is solely designed for making ICC profiles for scanner software will not make ICC profiles that work well with Capture One.

In most raw converters using ICC profiles the ICC profile works on linear input and applies itself the tone curve if you want one. In Capture One the input into the ICC profile is not linear, and the curve is not supposed to be applied by the profile, but separately by Capture One. To further complicate things the ICC profile is still expected to apply a minor amount of contrast, most significantly in the shadow range. Oh, and gamut compression too. A profile maker truly made for Capture One needs to take all these aspects into account. If it only is supposed to make reproduction profiles, like traditional profile makers do, some of these aspects can be skipped, but if you want to make a high-end general-purpose profile all aspects need to be taken into account, just as for Capture One's bundled profiles, which as you know are truly excellent -- if your taste is in line with the rather subjective look they provide.
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sebbe

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Re: Colorchecker ICC camera profiles
« Reply #9 on: January 10, 2019, 05:17:46 AM »

...

(Unfortunately Capture One v12 has currently a bug in the transfer function export so profile making doesn't work with that version yet, I guess X-Rite's software is affected too, so one have to use v11, the resulting profiles can still be used in v12 though)

May you explain what bug that is? I have v12 and v10. Therefore it would be no big deal for me to use an older version to create tifs for lumariver but it is good to know what the bug is.

To the x-rite software: It's good to see x-rite is taking C1 into account. But the software is still a big black box. The tethering shot with the CCPP in the video shows how serious they are about a good profile:
  • shadows of the shoes on part of the target
  • blue of the very close shoes will affect the very close rows
  • the picture itself is underexposed
  • the big softbox in the back will put a glare on the target (angle to the camera<45°)
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torger

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Re: Colorchecker ICC camera profiles
« Reply #10 on: January 10, 2019, 07:36:12 AM »

May you explain what bug that is? I have v12 and v10. Therefore it would be no big deal for me to use an older version to create tifs for lumariver but it is good to know what the bug is.

Sure: v12 exports random broken curves in the TIFFTAG_TRANSFERFUNCTION tag, and sometimes even crashes on export. This tag is only included if exporting for profiling, and is only used by third-party profile makers. It's an undocumented feature of Capture One that has existed for ages, with the purpose of supporting accurate third-party profiling. So it's sad that it wasn't properly tested before they released v12.

The transfer function is required to know how to linearize the data. In theory you could use hard-coded "Capture One Gamma", but as the linear curve used inside Capture One is not fully linear due to highlight clip handling etc (and differs between cameras) it doesn't exactly match up with the Capture One Gamma, so the only safe way to make accurate profiling is to apply the provided transfer function. And with v12 that function is trash :(. This should not only affect Lumariver Profile Designer but any other software making profiles for Capture One the proper way, that is doesn't use hard-coded approximate curves.

Phase One knows about this bug, but it's certainly not the only bug that needs fixing in v12 so maybe it will be a while before it works again. I have quite a number of Capture One users that uses Lumariver Profile Designer so I've got several "it's not working in v12" emails every week since the v12 release. Unfortunately I can't do anything about it other than referring to using an older version when making the profile (the profile is then compatible with v12), and wait for a fix. If your camera is only supported in v12 the only way is to wait for a fix, or manually attach a sane transfer function but then you can't be sure it is matching your camera exactly.
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sebbe

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Re: Colorchecker ICC camera profiles
« Reply #11 on: January 10, 2019, 09:00:30 AM »

Sure: v12 exports random broken curves in the TIFFTAG_TRANSFERFUNCTION tag, and sometimes even crashes on export. This tag is only included if exporting for profiling, and is only used by third-party profile makers. It's an undocumented feature of Capture One that has existed for ages, with the purpose of supporting accurate third-party profiling. So it's sad that it wasn't properly tested before they released v12.

The transfer function is required to know how to linearize the data. In theory you could use hard-coded "Capture One Gamma", but as the linear curve used inside Capture One is not fully linear due to highlight clip handling etc (and differs between cameras) it doesn't exactly match up with the Capture One Gamma, so the only safe way to make accurate profiling is to apply the provided transfer function. And with v12 that function is trash :(. This should not only affect Lumariver Profile Designer but any other software making profiles for Capture One the proper way, that is doesn't use hard-coded approximate curves.

Phase One knows about this bug, but it's certainly not the only bug that needs fixing in v12 so maybe it will be a while before it works again. I have quite a number of Capture One users that uses Lumariver Profile Designer so I've got several "it's not working in v12" emails every week since the v12 release. Unfortunately I can't do anything about it other than referring to using an older version when making the profile (the profile is then compatible with v12), and wait for a fix. If your camera is only supported in v12 the only way is to wait for a fix, or manually attach a sane transfer function but then you can't be sure it is matching your camera exactly.

Thanks you Anders for the information. It will also affect BasIIColors Input and this is supported by C1 or at least it is recommended to be used in the public color guide DTDCH.
Is it only with the export function? Or does it happen with the "edit with..." function too? And what about "linear scientific" curves? I'll do some tests this weekend.

Can you write us a bug description? I will report the bug too then. If more people ask they may give it more priority then.
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torger

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Re: Colorchecker ICC camera profiles
« Reply #12 on: January 10, 2019, 10:48:34 AM »

Thanks you Anders for the information. It will also affect BasIIColors Input and this is supported by C1 or at least it is recommended to be used in the public color guide DTDCH.
Is it only with the export function? Or does it happen with the "edit with..." function too? And what about "linear scientific" curves? I'll do some tests this weekend.

Can you write us a bug description? I will report the bug too then. If more people ask they may give it more priority then.

For critical work like professional reproduction, like most BasICColor users are working with as far as I understand, I would not recommend to upgrade immediately to big new major releases, at least not while keeping the old software and workflow working so there's a fallback. Capture One is far from unique when it comes to having some bugs in the "dot zero" major release, I've been a bit guilty myself in that regard :-[. But hopefully there will be some patch releases soon that starts fixing stuff users have reported in.

The bug description:

"When exporting a TIFF file for profiling the embedded transfer function (TIFFTAG_TRANSFERFUNCTION) contains seemingly random curve segments rather than the actual transfer function. This means that any third-party profile maker that depend on the transfer function to be able to linearize the image data can no longer make profiles. In my case the profile maker is XXX."

Be sure to test first though, I'm not 100% sure that the bug is manifested on all system+camera combinations, and I only want people that actually have a problem to send a report to Phase One.
If you are using Lumariver Profile Designer there's more information here http://www.lumariver.com/lrpd-manual/#c1_troubleshooting for example how you can use the tone curve dialog to actually plot the shape of the embedded transfer function, so you can see for sure that it's broken.

Edit: as shown below not all profile makers need the transfer function (X-Rite can do without). I was assuming that everyone did as the information has always been there. If the profile maker doesn't make use of the transfer function it must in some way estimate it, and it can do this using the target's neutral patches from black to white. I think that process is unnecessary when the information is there and is exact, but if Phase One is slow in fixing this bug I may need to reconsider...
« Last Edit: January 10, 2019, 02:15:06 PM by torger »
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torger

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Re: Colorchecker ICC camera profiles
« Reply #13 on: January 10, 2019, 12:25:53 PM »

Quick update, I just went by the office and briefly tested X-Rite profile maker. It is not dependent on the transfer function, so it can make profiles regardless. In fact I tested to strip the TIFF of both ICC and tags that even said it was generated by Capture One and it still made a profile, so it probably has no hard-coded information either. With no information of what linear is or what software that made the file I guess they make some estimate it from the color checker grayscale step in the image itself, which you of course can do if accuracy is not that important, curve fitting a gamma function would probably yield a quite good result, which they indeed do get. They probably have a large amount of smoothing involved too which make the profiling more robust for any kind of input errors.

The profile maker has no options whatsoever, so you don't really know what it does or what the intent of the profile is. However I made a reproduction profile with Lumariver Profile Designer for reference and compared it to what X-Rite makes, and indeed it does have the look of a reproduction profile as you would expect (this is what traditional profile makers have done in the past, linear reproduction, nothing else). Of course using such a profile with a curve does not yield a particularly good or perceptually accurate result, but how much it shows depends on subject material and I'm sure some will like it anyway. And for casual reproduction work it will make more accurate results than with the bundled Capture One profiles which are designed for general-purpose use and not reproduction, but of course you don't have the diagnostics and controls of more advanced software.
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torger

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Re: Colorchecker ICC camera profiles
« Reply #14 on: January 10, 2019, 01:07:00 PM »

The PDF that comes with the software refers to how to create profiles for capture one and how to prepare the original shot of color checker in Capture One for use in the the tool, it also has instructions on how to use the resulting ICC profile.
My first try is shown in pictures below, D700sun.jpg is with a color profile generated using the tool, D700Sun1.jpg is with the default CO D700 profile.  The most noticeable difference is in the dark blue patch, which is very similar to dng profiles created using the software with Lightroom.

The dark blue patch is a quite distinctive look of a reproduction profile. That blue patch on the color checker really is very dark so if you are making reproduction work (eg photographing a painting on canvas and then printing it on canvas) it should be that. However if you do general-purpose photography the deep blues will be so dark that tone reproduction suffers significantly, it's all just all to dark to make subtle gradations visible. Therefore almost no bundled profiles from a good quality raw converter renders blues like that, but instead lightens them significantly often paired with a little desaturation. It's just not a good idea to slap a curve on top of a linear reproduction profile and call it a general-purpose profile, and the overly dark deep blues is just one reason.

But well I'm getting on my hobby-horse now as I constantly talk about the importance of differing between linear reproduction and general-purpose when it comes to profiles. If you do want a neutral rendering with contrast, which product photographers want for example, the answer is still not a linear reproduction profile with a curve on top like X-Rite does here, that will over-saturate among other problems. The profile maker must take the final contrast into account to make a percetually neutral rendering.
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Dave Rosser

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Re: Colorchecker ICC camera profiles
« Reply #15 on: January 10, 2019, 02:56:25 PM »

The dark blue patch is a quite distinctive look of a reproduction profile. That blue patch on the color checker really is very dark so if you are making reproduction work (eg photographing a painting on canvas and then printing it on canvas) it should be that. However if you do general-purpose photography the deep blues will be so dark that tone reproduction suffers significantly, it's all just all to dark to make subtle gradations visible. Therefore almost no bundled profiles from a good quality raw converter renders blues like that, but instead lightens them significantly often paired with a little desaturation. It's just not a good idea to slap a curve on top of a linear reproduction profile and call it a general-purpose profile, and the overly dark deep blues is just one reason.

But well I'm getting on my hobby-horse now as I constantly talk about the importance of differing between linear reproduction and general-purpose when it comes to profiles. If you do want a neutral rendering with contrast, which product photographers want for example, the answer is still not a linear reproduction profile with a curve on top like X-Rite does here, that will over-saturate among other problems. The profile maker must take the final contrast into account to make a percetually neutral rendering.
Thanks for that explanation, the darkening of the blue patch is something that has puzzled me for years when using the x-rite software.

Dave

sebbe

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Re: Colorchecker ICC camera profiles
« Reply #16 on: January 15, 2019, 04:08:35 AM »

For critical work like professional reproduction, like most BasICColor users are working with as far as I understand, I would not recommend to upgrade immediately to big new major releases, at least not while keeping the old software and workflow working so there's a fallback. Capture One is far from unique when it comes to having some bugs in the "dot zero" major release, I've been a bit guilty myself in that regard :-[. But hopefully there will be some patch releases soon that starts fixing stuff users have reported in.

The bug description:

"When exporting a TIFF file for profiling the embedded transfer function (TIFFTAG_TRANSFERFUNCTION) contains seemingly random curve segments rather than the actual transfer function. This means that any third-party profile maker that depend on the transfer function to be able to linearize the image data can no longer make profiles. In my case the profile maker is XXX."

Be sure to test first though, I'm not 100% sure that the bug is manifested on all system+camera combinations, and I only want people that actually have a problem to send a report to Phase One.
If you are using Lumariver Profile Designer there's more information here http://www.lumariver.com/lrpd-manual/#c1_troubleshooting for example how you can use the tone curve dialog to actually plot the shape of the embedded transfer function, so you can see for sure that it's broken.

Edit: as shown below not all profile makers need the transfer function (X-Rite can do without). I was assuming that everyone did as the information has always been there. If the profile maker doesn't make use of the transfer function it must in some way estimate it, and it can do this using the target's neutral patches from black to white. I think that process is unnecessary when the information is there and is exact, but if Phase One is slow in fixing this bug I may need to reconsider...

The issue is present with my generated tiffs too. Beside Lumariver I tested BasICColor Input 5 too and it doesn't work either. Therefore I wrote the support of BasICColor and Phase One. Thanks for your explanations. Let's hope Phase One fix this soon.
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sebbe

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Re: Colorchecker ICC camera profiles
« Reply #17 on: January 15, 2019, 05:24:11 AM »

I had a reply from BasICColor support. They are aware of the issue and are in touch with Phase One which told them: "We have already addressed this bug and there will be a fix in a coming C1 release for this issue."  :D
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torger

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Re: Colorchecker ICC camera profiles
« Reply #18 on: January 16, 2019, 02:23:18 AM »

In the end of last week I asked Phase One support for progress on the issue and they gave me the same reply that the v12 bug will be fixed in their next patch release which is due out "soon". Interesting to hear about BasICColor. I hadn't tested their profile maker but I assumed they were affected too, which surely has helped in getting priority on the issue as their software is pretty big in professional reproduction so I'm sure they've got their fair share of support emails...
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torger

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Re: Colorchecker ICC camera profiles
« Reply #19 on: January 25, 2019, 07:49:37 AM »

I've heard the version 12.0.1 released a few days ago fixed the issue with the transfer function export so BasICColor and Lumariver profilers should work fine again, but I haven't had time to test for myself yet.

Edit: just tested, it works now.  :)
« Last Edit: January 25, 2019, 11:05:30 AM by torger »
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