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Author Topic: Shooting Color Targets  (Read 6357 times)
Vladimirovich
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« Reply #20 on: February 14, 2013, 08:49:58 PM »
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> if you will read Iliah Borg (who creates profiles for RPP) you will find out that that it is   ...

I can't find anything in that way on the RPP web site. Would you have a link?

sure, for example http://www.freelists.org/archive/argyllcms/  or if you can stomach http://translate.google.com then http://raw-rpp.livejournal.com

but then be warned, it might affect your self-esteem (regarding your abilities to get the job done)
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Vladimirovich
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« Reply #21 on: February 14, 2013, 08:59:17 PM »
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> I wrote to the author who said it does support DNG profiles

Oops! That must be of lately, I did not check that. Thanks Andrew.

Actually not ! RTFM

http://www.iridientdigital.com/products/rawdeveloper_history.html

1.7.0 - June 28, 2007

...Support for DNG metadata (2 color matrix) style camera color rendering in additional to existing support for ICC camera profiles....
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Hening Bettermann
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« Reply #22 on: February 15, 2013, 01:20:59 PM »
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ID supports the DNG format, to some degree, but not DNG profiles. I see no change to that in the current version 2. What Brian may have meant may have been that ID respects DNG profiles embedded in DNGs?
Good light!
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digitaldog
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« Reply #23 on: February 15, 2013, 01:32:52 PM »
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ID supports the DNG format, to some degree, but not DNG profiles. I see no change to that in the current version 2. What Brian may have meant may have been that ID respects DNG profiles embedded in DNGs?
Good light!


I've asked Brian to comment here but I can't guarantee he will (sometimes outside vendors are understandably uncomfortable doing so). I do have a reply email about this but again, I'd prefer to let Brian either comment or allow me to post his email to me.

I'm under the impression after a few days of conversation that one can use DNG profiles or ICC profiles in that product begging the question, which is 'better'?

I'm also of the opinion that making ICC camera profiles can be hit or miss, DNG profiles are nearly always a hit. IOW, the issues with ICC camera profiles over the years has been much worse than say making display, scanner or output profiles. That pretty much just works assuming a number of factors.

I think I can say that Brian feels ICC profiles are a better way to go and I hope we (meaning those on LuLa who are interested) could test this. But the creation of ICC profiles by end users has to be viable. It has to work all the time. At least as effectively as using a DNG profile. On paper, an ICC profile, it's color model and processing may be way better but if you build 10 and 4 are OK, doesn't matter what on paper is 'better'.
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Andrew Rodney
Author “Color Management for Photographers”
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Hening Bettermann
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« Reply #24 on: February 15, 2013, 02:14:14 PM »
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Vladimirovich,

In the Freelist archive, I see that Iliah Borg makes many contributions. But is there a place where he describes his procedure of profile creation in coherence?

Kind regards - Hening
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IliasG
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« Reply #25 on: February 15, 2013, 02:39:39 PM »
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Hi Henning,

http://translate.google.com/translate?sl=ru&tl=en&js=n&prev=_t&hl=el&ie=UTF-8&layout=2&eotf=1&u=http%3A%2F%2Fraw-rpp.livejournal.com%2F97552.html

http://translate.google.com/translate?sl=ru&tl=en&js=n&prev=_t&hl=el&ie=UTF-8&eotf=1&u=http%3A%2F%2Fsail2ithaki.livejournal.com%2F129988.html
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Hening Bettermann
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« Reply #26 on: February 15, 2013, 02:59:31 PM »
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Thank you IliasG!
The setup in the second link is pretty much like mine, except that I don't have dedicated reflectors - but white walls and white bed linnen...
The first link in fact contains that 1/3 figure:
"Do not fill the entire frame of the target, a third is sufficient for cameras with a resolution higher than 6 megapixels "
A useful link despite the bumps of the Google translation. Apart from the 1/3, it is pretty much what I'm doing.
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digitaldog
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« Reply #27 on: February 15, 2013, 05:08:48 PM »
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ID supports the DNG format, to some degree, but not DNG profiles. I see no change to that in the current version 2. What Brian may have meant may have been that ID respects DNG profiles embedded in DNGs?

Here's what I've gathered so far in terms of DNG profile support. The product doesn't support the latest DNG v1.4 spec that includes color table based profiles
When comparing this to an ICC profile, would those using DNG profiles cry foul if we were to limit the DNG profiles to color matrix data only?
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Andrew Rodney
Author “Color Management for Photographers”
http://digitaldog.net/
kirkt
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« Reply #28 on: February 15, 2013, 05:15:22 PM »
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Here is what Iliah Borg writes about target capture in the RPP user manual, pp. 33 and 34.

Quote
Lighting and Capturing the Target
by Iliah Borg
Properly capturing an evenly illuminated target is the most important aspect of camera profiling. Without a
quality shot of the target, the profiles will be poor - GIGO. The quality of the shot is more important than
having an expensive profiling target. The classic CC24, or ColorChecker Passport, or even a Mini CC is all
that is needed to start.
If you have a studio, you can use Solux 4700K lamps with black-painted backs or HMI lights (Mole-
Richardson is a good source). Broad-spectrum fluorescent lamps (Normlicht or JTI branded) are also a solid
choice. If you are on a budget, any halogen lamps with a stabilized power supply and gelled to reach about
5000K are OK.
For a decent setup, check http://www.imatest.com/docs/lab.html#lighting

You can also use daylight if a studio is out of reach. It is interesting to make different profiles for different
types of the daylight, and with different positions of the Sun.

1. To start, use as simple a lens as possible; a 50mm prime is ideal. You will need a separate profile for your
polarizing filter and also for CC40m and CC30m filters. Some lenses need a different profile, especially old
manual-focus primes. A good deep hood is a must; any reflections or flare will result in a poor profile. Clean
the sensor, the lens, the hood, and, of course, the filters if you are going to use them.
2. Affix the target on a gray card 2-3" larger than the target in each dimension. If the target is not perfectly
flat, the resulting profile will be compromised with shadows, colour casts, and uneven reflection. This is
very important for smaller targets like the Mini ColorChecker.
3. Do not fill the frame with the target. The target should occupy the middle 1/3 of the frame in each
dimension.
4. Cover the target with another gray card and set white balance from it. Remove the covering gray card and
blow away any dust from the profiling target.
5. Shoot at f/5.6 or thereabouts, very slightly out of focus.
6. Take a shot and ensure that readings from the gray card close to the four corners of the target are closely
clustered within a 6-point range. Be sure to cover the viewfinder to prevent the introduction of stray light.
7. Expose so that the whitest patch is in the range of 248-252 (250 is ideal). Take several shots bracketing
with shutter speed to ensure good results.

I use RPP (its implementation of the ArgyllCMS) to make ICC color profiles with the CC24 card, as well as the QP202 and QP203 cards. 

kirk
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Vladimirovich
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« Reply #29 on: February 15, 2013, 05:45:20 PM »
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Vladimirovich,

In the Freelist archive, I see that Iliah Borg makes many contributions. But is there a place where he describes his procedure of profile creation in coherence?

Kind regards - Hening

how about google for "iliah borg 1/3 frame target"... note that he wrote many times (and what you find is not necessarily the most recent and through instructions) about the procedures including for example acceptable limits of deviance in illumination of the target, etc... certainly what he writes is about getting "99%" vs "95%", but then if it a regular light then a decent raw converter for a modern camera shall already be supplied w/ a profile that is "95%" - unless you are seeking a placebo (look, I purchased a $100 target in a minute I did a shot and I put adobe's to shame... hurrah, hurrah... people all come start using my profile)
« Last Edit: February 15, 2013, 05:52:08 PM by Vladimirovich » Logged
digitaldog
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« Reply #30 on: February 15, 2013, 05:51:31 PM »
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Here is what Iliah Borg writes about target capture in the RPP user manual, pp. 33 and 34.

It's old, but I have no issues pasting what is in my book in terms of shooting a target:

Quote
Photographing the Targets
Naturally the target to be photographed should be clean and in good condition. Shooting the targets is fairly critical to the success and accuracy of the resulting profile. Once again, the debate among the experts comes into play here. Some experts suggest that all you have to do is set up a studio lighting environment and carefully photograph the targets whereas others suggest that the target must be included in each scene to properly profile how the camera records color. Let’s take the side of the experts who suggest that carefully photographing a camera target in the studio is the key to producing a single camera profile first.
In the studio, the best way to light the target is as evenly as possible to ensure no glare is seen on any of the patches. Placing some white tape to each edge of the target can make it easier to read the numeric values to ensure all four corners are lit as evenly as possible using Photoshop’s info palette. It is a good idea to place a large black sheet or cloth in front of the camera with a hole cut in the center large enough that the target can be seen by the camera. This black sheet of paper, cloth, or foam core will reduce stray light in other areas of the studio from hitting the target. Using black material behind and around the target is also recommended for the same reason. You want to ensure that no stray light bouncing off a colored object can fall onto the target. In such a situation, you can pho- tograph the target with one or two lights so that each corner of the target produces numeric values that are within a point or so as read by Photoshop’s (or a host software) info palette.
Some suggest that a single light be set as close to the lens axis as pos- sible whereas others suggest two lights at a 45-degree angle or what many photographers call “copy lighting.” The advantage to one light is that only one illuminant and color temperature is hitting the target; however, pro- ducing a high degree of even light is more difficult than using two lights. The downside of two lights is that even with electronic flash, finding two units that produce identical color temperatures is difficult. Some users have found that even a few degrees of color temperature difference in the lighting can cause issues with the resulting profile. To digress, I should point out that those users who wish to read the color temperature of either electronic flash or continuous lighting can do so with the Gretag- Macbeth Eye-One Pro Spectrophotometer and the accompanying Eye- One Share software. This can be a useful tool to see if the two lights for shooting the color target is within close specification. If the final studio situation is such that the photographer is photographing artwork and using polarizing filters over the lens or lights, it is important that the camera target photographed this way be measured with a Spectropho- tometer also using a polarizing filter, as this will affect the accuracy of the TDF. A Spectrophotometer, such as the GretagMacbeth Spectrolino allows a polarizing filter to measure a camera target.
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Andrew Rodney
Author “Color Management for Photographers”
http://digitaldog.net/
Vladimirovich
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« Reply #31 on: February 15, 2013, 05:52:59 PM »
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jesus, I was trying to make  him search !
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Vladimirovich
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« Reply #32 on: February 15, 2013, 05:54:12 PM »
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Apart from the 1/3, it is pretty much what I'm doing.

and then he probably will tell you that there are many sources of vignetting starting from lenses and all the way to the angle of the light when it hits the sensor...
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Vladimirovich
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« Reply #33 on: February 15, 2013, 05:55:46 PM »
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Here is what Iliah Borg writes about target capture in the RPP user manual, pp. 33 and 34.

unless RPP manual was updated (and I doubt) it is better to actually read the most recent postings in raw-rpp.livejournal.com there were changes vs the text of the manual
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Hening Bettermann
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« Reply #34 on: February 15, 2013, 06:33:32 PM »
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Thanks to all of you! This is the information I was looking for.
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Hening Bettermann
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« Reply #35 on: February 16, 2013, 04:05:31 PM »
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As for Iridient Developers support for DNG profiles: I have now tried it out with a DNG profile created by QPcard, and it is indeed recognized as a camera input profile.

Kirk:
> I use RPP (its implementation of the ArgyllCMS) to make ICC color profiles with the CC24 card, as well as the QP202 and QP203 cards. 

How do you do this? Argyll does not seem to support the QP202 card

http://www.argyllcms.com/doc/Scenarios.html#PS2
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Vladimirovich
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« Reply #36 on: February 16, 2013, 04:31:01 PM »
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How do you do this? Argyll does not seem to support the QP202 card

RPP has a GUI front end for Argyll and Iliah Borg supplied .cie files (agryll naturally will support any target that you describe)

just install RPP (no need to install Argyll separately by the way), make a small  donation (it is a donation ware - so profiling is locked - but even $0.01 will unlock it) and voila

« Last Edit: February 17, 2013, 10:22:09 AM by Vladimirovich » Logged
kirkt
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« Reply #37 on: February 16, 2013, 04:38:07 PM »
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RPP uses Argyll as its profiling engine.  The QP202 and 203 are supplied with the Lab values for each patch.  To make these profiling options available in the profiling dialog in RPP you simply need to make a ".cie" file for the particular target.  Attached are my files for the 202 and 203 - just open them in a text editor and edit the information (the originator, etc.).  You put these files in the location:

Code:
~/Library/Application\ Support/RPP/Profile\ Templates

and they will then become available choices in the Camera Profiling dialog dropdown menu.

kirk

EDIT - I cannot attach the text files so here is the formatted data for the QP203:

Code:
IT8.7/2
ORIGINATOR "Kirk Thibault"
DESCRIPTOR "QPCard 203"
CREATED  "Feb 06 2013"
MANUFACTURER "QPCard AB"

NUMBER_OF_FIELDS 4
BEGIN_DATA_FORMAT
SAMPLE_ID LAB_L LAB_A LAB_B
END_DATA_FORMAT

NUMBER_OF_SETS 35
BEGIN_DATA
A1 86.1 5.2 80.7
A2 81.9 26.1 74.6
A3 72.5 42.0 60.3
A4 85.1 -22.3 -6.0
A5 81.1 -20.7 14.6
A6 85.6 -11.4 33.1
A7 92.3 3.9 41.3
B1 56.1 28.4 -24.4
B2 43.0 51.0 22.5
B3 51.0 -48.7 14.2
B4 43.1 -18.2 -34.3
B5 72.5 -1.9 58.5
B6 54.1 -31.2 -23.4
B7 85.4 20.5 33.2
C1 55.1 35.3 -17.3
C2 44.0 55.1 15.3
C3 54.0 -46.8 25.3
C4 41.1 2.8 -46.4
C5 69.7 -11.9 54.2
C6 57.1 -41.4 -11.3
C7 82.5 24.7 16.1
D1 56.1 38.2 -6.2
D2 43.0 50.1 2.2
D3 52.0 -37.8 31.4
D4 39.1 13.6 -43.3
D5 65.5 -23.5 42.4
D6 55.0 -39.6 -1.1
D7 79.6 17.5 -8.9
E1 95.2 0.3 2.2
E2 85.2 0.3 2.4
E3 70.2 0.2 1.8
E4 59.1 0.2 1.0
E5 44.1 0.1 1.3
E6 34.1 0.1 1.4
E7 29.1 0.1 0.5

END_DATA
« Last Edit: February 16, 2013, 04:42:06 PM by kirkt » Logged
Vladimirovich
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« Reply #38 on: February 16, 2013, 05:06:19 PM »
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The QP202 and 203 are supplied with the Lab values for each patch.  To make these profiling options available in the profiling dialog in RPP you simply need to make a ".cie" file for the particular target.

author supplied his measurements actually - if they are not installed w/ recent versions RPP by default then here are links :

https://www.box.com/s/h4kyl0hl5hxx0xpudpr6

and

https://www.box.com/s/7jk96985segfyn1cpemm



and also for colorchecker sg = http://cl.ly/1u0s221n0v0f0s3G3J10/10deg_ColorChecker_DCSG.cie.zip



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samueljohnchia
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« Reply #39 on: February 16, 2013, 07:09:03 PM »
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I cannot attach the text files so here is the formatted data for the QP203:

Code:
IT8.7/2
ORIGINATOR "Kirk Thibault"
DESCRIPTOR "QPCard 203"
CREATED  "Feb 06 2013"
MANUFACTURER "QPCard AB"

NUMBER_OF_FIELDS 4
BEGIN_DATA_FORMAT
SAMPLE_ID LAB_L LAB_A LAB_B
END_DATA_FORMAT

NUMBER_OF_SETS 35
BEGIN_DATA
A1 86.1 5.2 80.7
A2 81.9 26.1 74.6
A3 72.5 42.0 60.3
A4 85.1 -22.3 -6.0
A5 81.1 -20.7 14.6
A6 85.6 -11.4 33.1
A7 92.3 3.9 41.3
B1 56.1 28.4 -24.4
B2 43.0 51.0 22.5
B3 51.0 -48.7 14.2
B4 43.1 -18.2 -34.3
B5 72.5 -1.9 58.5
B6 54.1 -31.2 -23.4
B7 85.4 20.5 33.2
C1 55.1 35.3 -17.3
C2 44.0 55.1 15.3
C3 54.0 -46.8 25.3
C4 41.1 2.8 -46.4
C5 69.7 -11.9 54.2
C6 57.1 -41.4 -11.3
C7 82.5 24.7 16.1
D1 56.1 38.2 -6.2
D2 43.0 50.1 2.2
D3 52.0 -37.8 31.4
D4 39.1 13.6 -43.3
D5 65.5 -23.5 42.4
D6 55.0 -39.6 -1.1
D7 79.6 17.5 -8.9
E1 95.2 0.3 2.2
E2 85.2 0.3 2.4
E3 70.2 0.2 1.8
E4 59.1 0.2 1.0
E5 44.1 0.1 1.3
E6 34.1 0.1 1.4
E7 29.1 0.1 0.5

END_DATA


This is the reference values from QP. I don't suggest using it. In my case it was found to be less accurate, especially for the lighter patches. Robin Myer's reference values gave a much better match. Vladimirovich posted the author's own measurements which are also better and more accurate than the OEM references.
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