Color management behaviour

[Leonardo Giordani]

Hi all,

I'm definitely lost with color management, I'm experiencing a number of issues (which I'm going to describe) and I do not understand where (if)
I'm doing something wrong.

I'm using digiKam 0.10.0 on Kubuntu Jaunty.

I refer to some screenshots you can find on Picasa ath the following address: sorry for the localized interface.

http://picasaweb.google.it/giordani.leonardo/DigiKam0100KubuntuJaunty#

My color management settings are:

Monitor: eye-made profile built with lprof (Samsung SyncMaster) - it is identical to an sRGB profile
Workspace: sRGB (since my monitor is limited)
Input: Canon Profile
Rendering: Perceptual

Since screenshots describe my workflow I'll comment them all.

01. First I start with a RAW file (.CR2) made by my Canon EOS 350D

02. I open it in Image Editor and digiKam ask me about "convert" or "assign" to current workspace profile (sRGB): since the source image is RAW
I choose "convert".

03. Here is my picture: it is a bit dark since the histogram (not shown in the screenshot, sorry) is concentrated on low keys.

04. If I try to deactivate color management (with the small bottom right icon) I obtain a picture with a brown look. You can see it on screenshot
number 09, where I compared the two side-by-side.

Question 1: why, if my monitor has am sRGB-like profile, does the picture change when I activate/deactivate color management?

05. After some work I obtain the final picture.

06. I save it as JPEG (aiming for example to Web publishing) and the small preview on the left side of the screen looks different, just like the
picture with color management deactivated.

07. When I close Image Editor I see that the preview of my JPEG has that brown look I did not have in Image Editor; the same happens with Gwenview or
any other image viewer. If I open it with The Gimp it says "The image has a color profile (sRGB), convert to sRGB built-in?". Both converting and letting
the original profile result in a correct image.

Question 2: why, if the built-in profile is the common sRGB, digiKam, Gwenview and others do not see it correctly? Why Gimp can? I understand that an
application cannot implement Color Management, but this is an sRGB profile, the "de-facto" standard when no color management is active. Or not?

08. If I try to open the JPEG with digiKam it keeps asking me if I want to convert or assign the sRGB color profile.

Question 3: why does digiKam not recognize the built in profile?

10. Now I try to deactivate color management. Picture in Image Editor looks different (understandable, without camera profile).

11. After some work I end up with a picture that, when saved, viewed with Gwenview, Gimp or whatever, is always identical.

Question 4: why now every application can see my picture correctly? I tried to move them on my laptop, which has a poor monitor, and I can barely see
the differences with my main monitor both in the color-managed picture and in the other one.

Thank you very much in advance for your answers, and thank you for digiKam

Leonardo

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Hi Leonardo,

I'm quite a newbie on color management, but I'll try to describe my setup and workflow in the hope it helps you.

I'm using an EOS 450D and digiKam 0.10.0 on openSuSE 11.1. The first thing with CR2 files is that they don't have an embedded or built-in color profile.

But, we need to tell digiKam which is the camera profile. I've been wandering a while with Digital Photo Professional (the raw converter/editor supplied by Canon). At least in mine, the camera profiles can be found under the folder

C:\Program Files\Canon\Digital Photo Professional\icc

There are in fact a pair of ICC profiles, one for sRGB color space and one for
AdobeRGB color space, for each picture style available

Faithful: fs.icc, fa.icc
Landscape: ls.icc, la.icc
Neutral: ns.icc, na.icc
Standard: ss.icc, sa.icc
Portrait: ps.icc, pa.icc

So if you work with sRGB colorspace, the suitable camera profiles should be fs.icc, ls.icc, ns.icc (*s.icc for sRGB), and so on. Copy them to /usr/share/color/icc under Linux and configure the path and preferred input profile on the Color Settings setup tab. These profiles are *not* identical to standard sRGB or Adobe RGB, they are specific to the camera model. This can be the reason you see the picture differently with/without color management.

As for the monitor profile, monitors come frequently with a "driver" in CD, part of which is the monitor's color profile. For example, I own an LG Flatron (not quite a good display as I would be pleased to have ;-) ). I searched on the driver CD and found the file lh1970hr.icm, which is the display profile for this particular model. As before, I copied this file to /usr/share/color/icc and selected it in digiKam setup. And as before, the monitor's profile is *not* identical to standard sRGB (although approximate), it is specific to the display model.

On the other hand, a distinction must be made between profiling and calibrating a monitor. Both are **essential** to have a good, or at least acceptable, color-managed workflow; otherwise you'll get under/overexposures while adjusting, as well as color shifts/casts. So in addition to getting a good monitor profile, you need to calibrate as much accurately as you can the monitor's black point, white point, and gamma. I suggest the methods described in the excellent tutorials and charts from Norman Koren at

http://www.normankoren.com/makingfineprints1A.html

which, if you don't need an extreme color accuracy, can be done "eyeball" without the need of a spectrometer.

Personally I always shot RAW in Adobe RGB colorspace, as it is a bit wider than sRGB and well suited for editing / printing. On the RAW converter I select the Landscape Adobe RGB input profile (la.icc) for general use, but change it when appropiate (pa.icc for portraits for example).

Once finished editing, I select Color -> Color Management, set Input Profile = Embedded profile, Workspace profile = sRGB and click OK to convert from Adobe to sRGB. Then I save the finished image in JPG or PNG format with sRGB embedded in it. In this way I see the picture OK in digiKam as well as in Gwenview or the GIMP.

Maybe the camera profiles are different for your 350D, but you can install Digital Photo Professional in a Windoze box, and use the filemon.exe utility from Micro$oft

http://technet.microsoft.com/en-us/sysinternals/bb896642.aspx

to investigate which files are opened/used during conversion and editing. One or more of them will be the camera profiles :-)

Wow, sorry for the length ;-) I hope that if something is wrong the "gurus" will reply with the truth (don't forget I'm also a newbie :-)), simply it works quite well for me.

Regards,

Francisco

On Viernes, 19 de Junio de 2009, Leonardo wrote:
Hi all,

I'm definitely lost with color management, I'm experiencing a number of issues (which I'm going to describe) and I do not understand where (if)
I'm doing something wrong.

I'm using digiKam 0.10.0 on Kubuntu Jaunty.

I refer to some screenshots you can find on Picasa ath the following address: sorry for the localized interface.

http://picasaweb.google.it/giordani.leonardo/DigiKam0100KubuntuJaunty#

My color management settings are:

Monitor: eye-made profile built with lprof (Samsung SyncMaster) - it is identical to an sRGB profile
Workspace: sRGB (since my monitor is limited)
Input: Canon Profile
Rendering: Perceptual

Since screenshots describe my workflow I'll comment them all.

01. First I start with a RAW file (.CR2) made by my Canon EOS 350D

02. I open it in Image Editor and digiKam ask me about "convert" or "assign" to current workspace profile (sRGB): since the source image is RAW
I choose "convert".

03. Here is my picture: it is a bit dark since the histogram (not shown in the screenshot, sorry) is concentrated on low keys.

04. If I try to deactivate color management (with the small bottom right icon) I obtain a picture with a brown look. You can see it on screenshot
number 09, where I compared the two side-by-side.

Question 1: why, if my monitor has am sRGB-like profile, does the picture change when I activate/deactivate color management?

05. After some work I obtain the final picture.

06. I save it as JPEG (aiming for example to Web publishing) and the small preview on the left side of the screen looks different, just like the
picture with color management deactivated.

07. When I close Image Editor I see that the preview of my JPEG has that brown look I did not have in Image Editor; the same happens with Gwenview or
any other image viewer. If I open it with The Gimp it says "The image has a color profile (sRGB), convert to sRGB built-in?". Both converting and letting
the original profile result in a correct image.

Question 2: why, if the built-in profile is the common sRGB, digiKam, Gwenview and others do not see it correctly? Why Gimp can? I understand that an
application cannot implement Color Management, but this is an sRGB profile, the "de-facto" standard when no color management is active. Or not?

08. If I try to open the JPEG with digiKam it keeps asking me if I want to convert or assign the sRGB color profile.

Question 3: why does digiKam not recognize the built in profile?

10. Now I try to deactivate color management. Picture in Image Editor looks different (understandable, without camera profile).

11. After some work I end up with a picture that, when saved, viewed with Gwenview, Gimp or whatever, is always identical.

Question 4: why now every application can see my picture correctly? I tried to move them on my laptop, which has a poor monitor, and I can barely see
the differences with my main monitor both in the color-managed picture and in the other one.

Thank you very much in advance for your answers, and thank you for digiKam

Leonardo

> Hi all,
>
> I'm definitely lost with color management, I'm experiencing a number of
> issues (which I'm going to describe) and I do not understand where (if) I'm
> doing something wrong.
>
> I'm using digiKam 0.10.0 on Kubuntu Jaunty.
>
> I refer to some screenshots you can find on Picasa ath the following
> address: sorry for the localized interface.
>
> http://picasaweb.google.it/giordani.leonardo/DigiKam0100KubuntuJaunty#
>
> My color management settings are:
>
> Monitor: eye-made profile built with lprof (Samsung SyncMaster) - it is
> identical to an sRGB profile Workspace: sRGB (since my monitor is limited)
> Input: Canon Profile
> Rendering: Perceptual
>
> Since screenshots describe my workflow I'll comment them all.
>
> 01. First I start with a RAW file (.CR2) made by my Canon EOS 350D
>
> 02. I open it in Image Editor and digiKam ask me about "convert" or
> "assign" to current workspace profile (sRGB): since the source image is RAW
> I choose "convert".
>
> 03. Here is my picture: it is a bit dark since the histogram (not shown in
> the screenshot, sorry) is concentrated on low keys.
>
> 04. If I try to deactivate color management (with the small bottom right
> icon) I obtain a picture with a brown look. You can see it on screenshot
> number 09, where I compared the two side-by-side.
>
> Question 1: why, if my monitor has am sRGB-like profile, does the picture
> change when I activate/deactivate color management?
>
> 05. After some work I obtain the final picture.
>
> 06. I save it as JPEG (aiming for example to Web publishing) and the small
> preview on the left side of the screen looks different, just like the
> picture with color management deactivated.
>
> 07. When I close Image Editor I see that the preview of my JPEG has that
> brown look I did not have in Image Editor; the same happens with Gwenview
> or any other image viewer. If I open it with The Gimp it says "The image
> has a color profile (sRGB), convert to sRGB built-in?". Both converting and
> letting the original profile result in a correct image.
>
> Question 2: why, if the built-in profile is the common sRGB, digiKam,
> Gwenview and others do not see it correctly? Why Gimp can? I understand
> that an application cannot implement Color Management, but this is an sRGB
> profile, the "de-facto" standard when no color management is active. Or
> not?
>
> 08. If I try to open the JPEG with digiKam it keeps asking me if I want to
> convert or assign the sRGB color profile.
>
> Question 3: why does digiKam not recognize the built in profile?
>
> 10. Now I try to deactivate color management. Picture in Image Editor looks
> different (understandable, without camera profile).
>
> 11. After some work I end up with a picture that, when saved, viewed with
> Gwenview, Gimp or whatever, is always identical.
>
> Question 4: why now every application can see my picture correctly? I tried
> to move them on my laptop, which has a poor monitor, and I can barely see
> the differences with my main monitor both in the color-managed picture and
> in the other one.
>
> Thank you very much in advance for your answers, and thank you for digiKam
>
> Leonardo

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[Milan Knížek]

Hi Francisco,

Francisco Lorés Ara píše v Pá 19. 06. 2009 v 19:05 +0200:

> There are in fact a pair of ICC profiles, one for sRGB color space and
> one for
> AdobeRGB color space, for each picture style available
>
>
>
> Faithful: fs.icc, fa.icc
> Landscape: ls.icc, la.icc
> Neutral: ns.icc, na.icc
> Standard: ss.icc, sa.icc
> Portrait: ps.icc, pa.icc
>
>
>
> So if you work with sRGB colorspace, the suitable camera profiles
> should be fs.icc, ls.icc, ns.icc (*s.icc for sRGB), and so on. Copy
> them to /usr/share/color/icc under Linux and configure the path and
> preferred input profile on the Color Settings setup tab. These
> profiles are *not* identical to standard sRGB or Adobe RGB, they are
> specific to the camera model. This can be the reason you see the
> picture differently with/without color management.
>

Would you mind emailing me any pair of the profiles provided by Canon?
(Eg. fs.icc and fa.icc)

I wonder, how these are different. Generally, selecting the colour space
in the camera should not affect the RAW file (because it is raw data),
but it should affect the JPEG files only or be included in exif maker
notes to tell the vendor software to which colour space the raw should
be converted.

P.S. BTW, use of Canon's profiles may not be the best option since these
profiles were built for Canon's software, not for digiKam's raw
converter. However, if the output is satisfactory, it is better than
nothing.

Thanks,


Milan Knizek
knizek (dot) confy (at) volny (dot) cz
http://www.milan-knizek.net - About linux and photography (Czech
language only)

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[Paul Waldo]

That's what I was thinking.  I'm guessing that the profiles get applied to the jpegs that accompany the raws.

Paul
----- "Milan Knížek" <[hidden email]> wrote:

> I wonder, how these are different. Generally, selecting the colour
> space
> in the camera should not affect the RAW file (because it is raw data),
> but it should affect the JPEG files only or be included in exif maker
> notes to tell the vendor software to which colour space the raw should
> be converted.
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[Francesco Scaglioni-2]

Hi,

,------[ Milan said ::  ]
| P.S. BTW, use of Canon's profiles may not be the best option
| since these profiles were built for Canon's software, not
| for digiKam's raw converter. However, if the output is
| satisfactory, it is better than nothing.
`------

Any thoughts on how one might determine or obtain profiles
that are more suited.  I too have been using those supplied
by canon and am always looking for ways to improve my setup.

Many thanks,


F
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Hi,

I have also experimented with some profiles from Bibble. This software has profiles for a large nuber of brands and models. Some of them work quite well; in my case (Canon EOS 450D) the file canonc.icm is best suited with digiKam. (i wonder if this use of the profiles might create legal issues; if anyone have information, please let me know), However, all these are "blind" tests as the profiles don't have inside the brand/model camera information. You'll need to trust your eyes :-)

As a general rule, it seems that the only way to obtain profiles is from manufacturer's or third parties software, and these will be at best approximate. "The" profile could only be obtained by means of a spectrocolorimeter... :-(

Best for everyone

Francisco

On Sábado, 20 de Junio de 2009, Francesco wrote:
Hi,

,------[ Milan said :: ]
| P.S. BTW, use of Canon's profiles may not be the best option
| since these profiles were built for Canon's software, not
| for digiKam's raw converter. However, if the output is
| satisfactory, it is better than nothing.
`------

Any thoughts on how one might determine or obtain profiles
that are more suited. I too have been using those supplied
by canon and am always looking for ways to improve my setup.

Many thanks,

F
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> Hi,
>
> ,------[ Milan said :: ]
>
> | P.S. BTW, use of Canon's profiles may not be the best option
> | since these profiles were built for Canon's software, not
> | for digiKam's raw converter. However, if the output is
> | satisfactory, it is better than nothing.
>
> `------
>
> Any thoughts on how one might determine or obtain profiles
> that are more suited. I too have been using those supplied
> by canon and am always looking for ways to improve my setup.
>
> Many thanks,
>
>
> F
> _______________________________________________
> Digikam-users mailing list
> [hidden email]
> https://mail.kde.org/mailman/listinfo/digikam-users

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[Milan Knížek]

Hi,

Francesco Scaglioni píše v So 20. 06. 2009 v 10:28 +0100:

> Any thoughts on how one might determine or obtain profiles
> that are more suited.  I too have been using those supplied
> by canon and am always looking for ways to improve my setup.
>
No simple answer here.

One approach is to obtain a colorimetric target (like IT8.7) and prepare
own profile for the particular workflow (using argyllcms, lprof - the
process is similar to profiling a scanner).

Another approach is to rely on vendor of the software - like Bibble with
its own profiles or UFRaw with colour matrix.

I am using both and while for some pictures I find more pleasing results
are from my own profile, for others I prefer UFRaw's colour matrix
(actually, these come from dcraw and are probably comparable to those
used by Adobe raw converter). Note that I am saying "pleasing" results
since I do not do a colour reproduction work.

The critical points with own profiles are: changing type and colour of
light (sun, shade, bulb, etc.), material from which the target is made
(metamerism, different colour reproduction when compared to a real
scene), number of colours of the target (the rest is
inter/extrapolated), camera sensor linearity (any error means the
extra/interpolation may be wrong), adjustments to raw/rgb data before
application of the profile (white-balancing, EV or tonal adjustment).
Definitely not an easy thing.

You may want to look at argyllcms list archive - these topics are
occasionally discussed there.

Also a good reading is "ICC White Paper #17" (use google to find it)

Hope it helps,

Milan Knizek
knizek (dot) confy (at) volny (dot) cz
http://www.milan-knizek.net - About linux and photography (Czech
language only)

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[Leonardo Giordani]

Francisco,

thank you for you advices. I notice some inconsistency in color management, though. My issues happen if I click on my RAW picture and open it with "modify"; but if I use RAW importer as you suggested color management works as expected.

Developers, something to say about this?

Summary: opening a RAW data asks for "Assign" or "Convert" to workspace, but it works differently from how RAW importer works.

Someone is experiencing the same issue (and the issues I talk about in my first mail?)

Thanks

Leonardo

2009/6/19 Francisco Lorés Ara <[hidden email]>

Hi Leonardo,

I'm quite a newbie on color management, but I'll try to describe my setup and workflow in the hope it helps you.

I'm using an EOS 450D and digiKam 0.10.0 on openSuSE 11.1. The first thing with CR2 files is that they don't have an embedded or built-in color profile.

But, we need to tell digiKam which is the camera profile. I've been wandering a while with Digital Photo Professional (the raw converter/editor supplied by Canon). At least in mine, the camera profiles can be found under the folder

C:\Program Files\Canon\Digital Photo Professional\icc

There are in fact a pair of ICC profiles, one for sRGB color space and one for
AdobeRGB color space, for each picture style available

Faithful: fs.icc, fa.icc
Landscape: ls.icc, la.icc
Neutral: ns.icc, na.icc
Standard: ss.icc, sa.icc
Portrait: ps.icc, pa.icc

So if you work with sRGB colorspace, the suitable camera profiles should be fs.icc, ls.icc, ns.icc (*s.icc for sRGB), and so on. Copy them to /usr/share/color/icc under Linux and configure the path and preferred input profile on the Color Settings setup tab. These profiles are *not* identical to standard sRGB or Adobe RGB, they are specific to the camera model. This can be the reason you see the picture differently with/without color management.

As for the monitor profile, monitors come frequently with a "driver" in CD, part of which is the monitor's color profile. For example, I own an LG Flatron (not quite a good display as I would be pleased to have ;-) ). I searched on the driver CD and found the file lh1970hr.icm, which is the display profile for this particular model. As before, I copied this file to /usr/share/color/icc and selected it in digiKam setup. And as before, the monitor's profile is *not* identical to standard sRGB (although approximate), it is specific to the display model.

On the other hand, a distinction must be made between profiling and calibrating a monitor. Both are **essential** to have a good, or at least acceptable, color-managed workflow; otherwise you'll get under/overexposures while adjusting, as well as color shifts/casts. So in addition to getting a good monitor profile, you need to calibrate as much accurately as you can the monitor's black point, white point, and gamma. I suggest the methods described in the excellent tutorials and charts from Norman Koren at

http://www.normankoren.com/makingfineprints1A.html

which, if you don't need an extreme color accuracy, can be done "eyeball" without the need of a spectrometer.

Personally I always shot RAW in Adobe RGB colorspace, as it is a bit wider than sRGB and well suited for editing / printing. On the RAW converter I select the Landscape Adobe RGB input profile (la.icc) for general use, but change it when appropiate (pa.icc for portraits for example).

Once finished editing, I select Color -> Color Management, set Input Profile = Embedded profile, Workspace profile = sRGB and click OK to convert from Adobe to sRGB. Then I save the finished image in JPG or PNG format with sRGB embedded in it. In this way I see the picture OK in digiKam as well as in Gwenview or the GIMP.

Maybe the camera profiles are different for your 350D, but you can install Digital Photo Professional in a Windoze box, and use the filemon.exe utility from Micro$oft

http://technet.microsoft.com/en-us/sysinternals/bb896642.aspx

to investigate which files are opened/used during conversion and editing. One or more of them will be the camera profiles :-)

Wow, sorry for the length ;-) I hope that if something is wrong the "gurus" will reply with the truth (don't forget I'm also a newbie :-)), simply it works quite well for me.

Regards,

Francisco

--
Leonardo Giordani

Tele-Rilevamento Europa - T.R.E. s.r.l.
a POLIMI spin-off company
Via Vittoria Colonna, 7
20149 Milano - Italia
tel.: [phone]
fax: [phone]
e-mail: leonardo.giordani (at) treuropa.com
web: www.treuropa.com

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[Gilles Caulier-4]

2009/6/22 Leonardo Giordani <[hidden email]>:
> Francisco,
>
> thank you for you advices. I notice some inconsistency in color management,
> though. My issues happen if I click on my RAW picture and open it with
> "modify"; but if I use RAW importer as you suggested color management works
> as expected.
>
> Developers, something to say about this?

yes. Sound like something is broken in CM.

There are few entry in bugzilla about this subject. sound like code is
broken somewhere when port to Qt4 have been done.

I will review code before 1.0.0 final release. For the moment i'm busy
on other place (:=)))

Gilles Caulier

>
> Summary: opening a RAW data asks for "Assign" or "Convert" to workspace, but
> it works differently from how RAW importer works.
>
> Someone is experiencing the same issue (and the issues I talk about in my
> first mail?)
>
> Thanks
>
> Leonardo
>
> 2009/6/19 Francisco Lorés Ara <[hidden email]>
>>
>> Hi Leonardo,
>>
>> I'm quite a newbie on color management, but I'll try to describe my setup
>> and workflow in the hope it helps you.
>>
>> I'm using an EOS 450D and digiKam 0.10.0 on openSuSE 11.1. The first thing
>> with CR2 files is that they don't have an embedded or built-in color
>> profile.
>>
>> But, we need to tell digiKam which is the camera profile. I've been
>> wandering a while with Digital Photo Professional (the raw converter/editor
>> supplied by Canon). At least in mine, the camera profiles can be found under
>> the folder
>>
>> C:\Program Files\Canon\Digital Photo Professional\icc
>>
>> There are in fact a pair of ICC profiles, one for sRGB color space and one
>> for
>> AdobeRGB color space, for each picture style available
>>
>> Faithful: fs.icc, fa.icc
>> Landscape: ls.icc, la.icc
>> Neutral: ns.icc, na.icc
>> Standard: ss.icc, sa.icc
>> Portrait: ps.icc, pa.icc
>>
>> So if you work with sRGB colorspace, the suitable camera profiles should
>> be fs.icc, ls.icc, ns.icc (*s.icc for sRGB), and so on. Copy them to
>> /usr/share/color/icc under Linux and configure the path and preferred input
>> profile on the Color Settings setup tab. These profiles are *not* identical
>> to standard sRGB or Adobe RGB, they are specific to the camera model. This
>> can be the reason you see the picture differently with/without color
>> management.
>>
>> As for the monitor profile, monitors come frequently with a "driver" in
>> CD, part of which is the monitor's color profile. For example, I own an LG
>> Flatron (not quite a good display as I would be pleased to have ;-) ). I
>> searched on the driver CD and found the file lh1970hr.icm, which is the
>> display profile for this particular model. As before, I copied this file to
>> /usr/share/color/icc and selected it in digiKam setup. And as before, the
>> monitor's profile is *not* identical to standard sRGB (although
>> approximate), it is specific to the display model.
>>
>> On the other hand, a distinction must be made between profiling and
>> calibrating a monitor. Both are **essential** to have a good, or at least
>> acceptable, color-managed workflow; otherwise you'll get under/overexposures
>> while adjusting, as well as color shifts/casts. So in addition to getting a
>> good monitor profile, you need to calibrate as much accurately as you can
>> the monitor's black point, white point, and gamma. I suggest the methods
>> described in the excellent tutorials and charts from Norman Koren at
>>
>> http://www.normankoren.com/makingfineprints1A.html
>>
>> which, if you don't need an extreme color accuracy, can be done "eyeball"
>> without the need of a spectrometer.
>>
>> Personally I always shot RAW in Adobe RGB colorspace, as it is a bit wider
>> than sRGB and well suited for editing / printing. On the RAW converter I
>> select the Landscape Adobe RGB input profile (la.icc) for general use, but
>> change it when appropiate (pa.icc for portraits for example).
>>
>> Once finished editing, I select Color -> Color Management, set Input
>> Profile = Embedded profile, Workspace profile = sRGB and click OK to convert
>> from Adobe to sRGB. Then I save the finished image in JPG or PNG format with
>> sRGB embedded in it. In this way I see the picture OK in digiKam as well as
>> in Gwenview or the GIMP.
>>
>> Maybe the camera profiles are different for your 350D, but you can install
>> Digital Photo Professional in a Windoze box, and use the filemon.exe utility
>> from Micro$oft
>>
>> http://technet.microsoft.com/en-us/sysinternals/bb896642.aspx
>>
>> to investigate which files are opened/used during conversion and editing.
>> One or more of them will be the camera profiles :-)
>>
>>
>> Wow, sorry for the length ;-) I hope that if something is wrong the
>> "gurus" will reply with the truth (don't forget I'm also a newbie :-)),
>> simply it works quite well for me.
>>
>> Regards,
>>
>> Francisco
>>
>>
>
> --
> Leonardo Giordani
>
> Tele-Rilevamento Europa - T.R.E. s.r.l.
> a POLIMI spin-off company
> Via Vittoria Colonna, 7
> 20149 Milano - Italia
> tel.: [phone]
> fax: [phone]
> e-mail: leonardo.giordani (at) treuropa.com
> web: www.treuropa.com
>
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> https://mail.kde.org/mailman/listinfo/digikam-users
>
>

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[Leonardo Giordani]

Ok, thank you Gilles. Do you need a good summary of the issues? I mean screenshots and test cases?

Leonardo

2009/6/22 Gilles Caulier <[hidden email]>

2009/6/22 Leonardo Giordani <[hidden email]>:
> Francisco,
>

> thank you for you advices. I notice some inconsistency in color management,
> though. My issues happen if I click on my RAW picture and open it with
> "modify"; but if I use RAW importer as you suggested color management works
> as expected.
>
> Developers, something to say about this?

yes. Sound like something is broken in CM.

There are few entry in bugzilla about this subject. sound like code is
broken somewhere when port to Qt4 have been done.

I will review code before 1.0.0 final release. For the moment i'm busy
on other place (:=)))

Gilles Caulier

>
> Summary: opening a RAW data asks for "Assign" or "Convert" to workspace, but
> it works differently from how RAW importer works.
>
> Someone is experiencing the same issue (and the issues I talk about in my
> first mail?)
>
> Thanks
>
> Leonardo
>
> 2009/6/19 Francisco Lorés Ara <[hidden email]>
>>
>> Hi Leonardo,
>>
>> I'm quite a newbie on color management, but I'll try to describe my setup
>> and workflow in the hope it helps you.
>>
>> I'm using an EOS 450D and digiKam 0.10.0 on openSuSE 11.1. The first thing
>> with CR2 files is that they don't have an embedded or built-in color
>> profile.
>>
>> But, we need to tell digiKam which is the camera profile. I've been
>> wandering a while with Digital Photo Professional (the raw converter/editor
>> supplied by Canon). At least in mine, the camera profiles can be found under
>> the folder
>>
>> C:\Program Files\Canon\Digital Photo Professional\icc
>>
>> There are in fact a pair of ICC profiles, one for sRGB color space and one
>> for
>> AdobeRGB color space, for each picture style available
>>
>> Faithful: fs.icc, fa.icc
>> Landscape: ls.icc, la.icc
>> Neutral: ns.icc, na.icc
>> Standard: ss.icc, sa.icc
>> Portrait: ps.icc, pa.icc
>>
>> So if you work with sRGB colorspace, the suitable camera profiles should
>> be fs.icc, ls.icc, ns.icc (*s.icc for sRGB), and so on. Copy them to
>> /usr/share/color/icc under Linux and configure the path and preferred input
>> profile on the Color Settings setup tab. These profiles are *not* identical
>> to standard sRGB or Adobe RGB, they are specific to the camera model. This
>> can be the reason you see the picture differently with/without color
>> management.
>>
>> As for the monitor profile, monitors come frequently with a "driver" in
>> CD, part of which is the monitor's color profile. For example, I own an LG
>> Flatron (not quite a good display as I would be pleased to have ;-) ). I
>> searched on the driver CD and found the file lh1970hr.icm, which is the
>> display profile for this particular model. As before, I copied this file to
>> /usr/share/color/icc and selected it in digiKam setup. And as before, the
>> monitor's profile is *not* identical to standard sRGB (although
>> approximate), it is specific to the display model.
>>
>> On the other hand, a distinction must be made between profiling and
>> calibrating a monitor. Both are **essential** to have a good, or at least
>> acceptable, color-managed workflow; otherwise you'll get under/overexposures
>> while adjusting, as well as color shifts/casts. So in addition to getting a
>> good monitor profile, you need to calibrate as much accurately as you can
>> the monitor's black point, white point, and gamma. I suggest the methods
>> described in the excellent tutorials and charts from Norman Koren at
>>
>> http://www.normankoren.com/makingfineprints1A.html
>>
>> which, if you don't need an extreme color accuracy, can be done "eyeball"
>> without the need of a spectrometer.
>>
>> Personally I always shot RAW in Adobe RGB colorspace, as it is a bit wider
>> than sRGB and well suited for editing / printing. On the RAW converter I
>> select the Landscape Adobe RGB input profile (la.icc) for general use, but
>> change it when appropiate (pa.icc for portraits for example).
>>
>> Once finished editing, I select Color -> Color Management, set Input
>> Profile = Embedded profile, Workspace profile = sRGB and click OK to convert
>> from Adobe to sRGB. Then I save the finished image in JPG or PNG format with
>> sRGB embedded in it. In this way I see the picture OK in digiKam as well as
>> in Gwenview or the GIMP.
>>
>> Maybe the camera profiles are different for your 350D, but you can install
>> Digital Photo Professional in a Windoze box, and use the filemon.exe utility
>> from Micro$oft
>>
>> http://technet.microsoft.com/en-us/sysinternals/bb896642.aspx
>>
>> to investigate which files are opened/used during conversion and editing.
>> One or more of them will be the camera profiles :-)
>>
>>
>> Wow, sorry for the length ;-) I hope that if something is wrong the
>> "gurus" will reply with the truth (don't forget I'm also a newbie :-)),
>> simply it works quite well for me.
>>
>> Regards,
>>
>> Francisco
>>
>>
>
> --
> Leonardo Giordani
>
> Tele-Rilevamento Europa - T.R.E. s.r.l.
> a POLIMI spin-off company
> Via Vittoria Colonna, 7
> 20149 Milano - Italia
> tel.: [phone]
> fax: [phone]
> e-mail: leonardo.giordani (at) treuropa.com
> web: www.treuropa.com
>

> _______________________________________________
> Digikam-users mailing list
> [hidden email]
> https://mail.kde.org/mailman/listinfo/digikam-users
>
>
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--
Leonardo Giordani

Tele-Rilevamento Europa - T.R.E. s.r.l.
a POLIMI spin-off company
Via Vittoria Colonna, 7
20149 Milano - Italia
tel.: [phone]
fax: [phone]
e-mail: leonardo.giordani (at) treuropa.com
web: www.treuropa.com

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[Gilles Caulier-4]

2009/6/22 Leonardo Giordani <[hidden email]>:
> Ok, thank you Gilles. Do you need a good summary of the issues? I mean
> screenshots and test cases?

Not yet, but later, when i will fix all CM entries in B.K., i will
need regression tests from users.

If you want to help in this way, it simple : take a look here,

https://bugs.kde.org/buglist.cgi?query_format=advanced&short_desc_type=allwordssubstr&short_desc=&product=digikam&component=Color+Management&long_desc_type=substring&long_desc=&bug_file_loc_type=allwordssubstr&bug_file_loc=&keywords_type=allwords&keywords=&bug_status=UNCONFIRMED&bug_status=NEW&bug_status=ASSIGNED&bug_status=REOPENED&emailassigned_to1=1&emailtype1=substring&email1=&emailassigned_to2=1&emailreporter2=1&emailcc2=1&emailtype2=substring&email2=&bugidtype=include&bug_id=&votes=&chfieldfrom=&chfieldto=Now&chfieldvalue=&cmdtype=doit&order=Reuse+same+sort+as+last+time&field0-0-0=noop&type0-0-0=noop&value0-0-0=

There are 16 entries. You can take a look which still valid with
current implementation from svn (1.0.0-beta2). In beta2, we have more
than 40 new bugs closed.

For all valid entries, just set your e-mail as CC to have news when
code will be fixed and ready to test.

Thanks in advance

Note : for the moment, i'm busy with all metadata relevant entries. I
would to fix bugs before next Exiv2 0.18.2 release.

Gilles Caulier
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[Geert Janssens]

On Monday 22 June 2009, Gilles Caulier wrote:

> 2009/6/22 Leonardo Giordani <[hidden email]>:
> > Ok, thank you Gilles. Do you need a good summary of the issues? I mean
> > screenshots and test cases?
>
> Not yet, but later, when i will fix all CM entries in B.K., i will
> need regression tests from users.
>
> If you want to help in this way, it simple : take a look here,
>
> https://bugs.kde.org/buglist.cgi?query_format=advanced&short_desc_type=allw
>ordssubstr&short_desc=&product=digikam&component=Color+Management&long_desc_
>type=substring&long_desc=&bug_file_loc_type=allwordssubstr&bug_file_loc=&key
>words_type=allwords&keywords=&bug_status=UNCONFIRMED&bug_status=NEW&bug_stat
>us=ASSIGNED&bug_status=REOPENED&emailassigned_to1=1&emailtype1=substring&ema
>il1=&emailassigned_to2=1&emailreporter2=1&emailcc2=1&emailtype2=substring&em
>ail2=&bugidtype=include&bug_id=&votes=&chfieldfrom=&chfieldto=Now&chfieldval
>ue=&cmdtype=doit&order=Reuse+same+sort+as+last+time&field0-0-0=noop&type0-0-
>0=noop&value0-0-0=
>
> There are 16 entries. You can take a look which still valid with
> current implementation from svn (1.0.0-beta2). In beta2, we have more
> than 40 new bugs closed.
>

I think bug 186054 (https://bugs.kde.org/show_bug.cgi?id=186054) is also color
management related, but I filed it under the Image Editor component.
Unfortunatly it won't show up in the list of open Color Management bugs like
this. Maybe someone can assign it to the proper component ? I don't have the
permissions to do so.

Thank you.

Geert
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