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I installed a setup, and I shot three photos with the same f/1.7 1/100s ISO100 condition:

How to use the Xrite Colorchecker (in photos A or B) to get calibrated colors, so that photo C will have proper colors?

Tools: Photoshop + Camera Raw + "ColorChecker Camera Calibration software v 2" (from Xrite), or any other freeware, but not Lightroom

Note: I've read many blog posts, tutorials, but it does not look so simple to do, thus this question ; please note that I don't want to make a "profile" for future use with this camera, but only to modify the colors for this specific picture / these specific lighting conditions.

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Your colour checker is incorrectly lit and placed here. The lighting should be as uniform as possible and representative of the illumination conditions of your subject.

Generally speaking, however, you should only really use the colour checker for white balancing and exposure correction. It is very tempting to use is systematically for colour correction but you will most likely generate a correction matrix that is worse than those the camera vendor or Adobe provides. The matrix you generate will attempt to match the colour checker colours for your particular illumination conditions but those are entirely different than that used to measure the reference colour checker values. As a result, and once the matrix applied, the colour checker will effectively look better but your object colour might be worse. The explanation as to why is beyond the scope of this answer but beside proper lighting and geometry of the colour checker in your scene, you have to consider Metamerism.

If you are willing to get your hands a bit greasy and don't mind coding, you can try Colour - Checker Detection, this notebook has an example on how to perform the colour correction.

If you are really interested in that topic, Procedure P-2013-001 Recommended Procedures for the Creation and Use of Digital Camera System Input Device Transforms (IDTs) specifies a procedure to do perform the characterisation of cameras and there is a companion thread testing the procedure on ACES Central.

  • You're right about the placement of the colorchecker, I'll re-do a shooting with a better placement. – Basj Nov 3 at 20:26
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Here is a useful tutorial, and a documentation in PDF: White Balance and Colour Calibration Workflow in Photoshop with the X -Rite ColorChecker Passport (Adobe Camera Raw 10.3 and Later).

The workflow is:

  1. Shoot in RAW or DNG an image with the Colorchecker visible with good lighting
  2. If needed, convert the RAW to DNG (either using Lightroom > Export > Filetype > DNG or using DNG converter
  3. Use Xrite's "Colorchecker Camera Calibration" software in DNG mode to open the photo
  4. Save the exported profile as .dcp file in C:\Users\User\AppData\Roaming\Adobe\CameraRaw\CameraProfiles
  5. Open the image in CameraRaw and choose the profile in the Profile Browser:

  6. Working!


Failing methods I've tried (when using JPG or TIFF files):

  • Use Xrite's "Colorchecker Camera Calibration" software in TIFF mode (from a JPG converted to TIFF). The output is an .icm file, and I haven't found how to use this .icm in Photoshop or CameraRaw

  • Convert a JPG to DNG with DNG Converter: not working

  • Convert a JPG to DNG with Lightroom > Export: working, but:

    • this DNG cannot be read in Xrite's "Colorchecker Camera Calibration"

    • this DNG can be opened by Adobe's DNG_Profile_Editor_win_1_0_4.exe, and the latter can detect the Colorchecker and output a .dcp or .dcpr. But unfortunately, even when copying this .dcp in C:\Users\User\AppData\Roaming\Adobe\CameraRaw\CameraProfiles, this profile doesn't appear in the Profile Browser when opening CameraRaw with a JPG/TIFF

Conclusion: it doesn't work at all with JPG/TIFF (or JPG/TIFF converted to DNG), but it works with true RAW/DNG files.


Other methods I've tried (when using DNG files as input):

  • Use Adobe's DNG_Profile_Editor_win_1_0_4.exe: the output .dcp profile gives another color rendering than the one I obtain with Xrite's "Colorchecker Camera Calibration", when using it in CameraRaw.
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Consider this answer as an addendum, not as a direct answer for the color checker usage.

And I am writing it because your posted images are showing some important deficiencies.

To get the right colors you need a bit more than just the color checker. In fact, it is probably the last step, not the only or primary one.

Illumination

Not only they need to be in a consistent spot, avoiding reflections and unwanted shadows, but consistency across your photo. Be aware of any fall of because of the distance from the light source.

Your lights should have a good enough CRI, Color Rendition Index, so use some good quality lights. Avoid Fluorescent or cheap LEDs. Use a flash if possible.

White balance

Define the white balance of the light setup.

I don't want to make a "profile" for future use with this camera...these specific lighting conditions.

A profile is made for a combination of Camera + Lens + Light setup, including ambient light if it is relevant. If you change any of them, you should redefine at least the white balance. (Or make a new profile since you have already a checker)

Here is the first usage of the color checker. Use the gray targets to define the white balance, but personally I prefer using some other methods to do this, mainly taking the picture of my main softbox.

Exposition

Here it is another major issue on your light setup, they are way underexposed. You will only have a lot of noise when you adjust it.

You need to know your camera, if your camera gives you a reading of X aperture and Y speed, taking the photo of a white background and render it as gray, you need to know how many stops or speed you need to increase to make the white look white without cropping it. Depending on the camera and the look you want, you could use 3 stops brighter than the base reading. The histogram is your BEST friend.

Position of target

It should be in the middle of the framing your product will be. Put it on the pillow. This is closely related to point 1, fall off, ambient light contamination, etc.

Take the photo and

Yeap, you do not use it only for the image you want to correct. You need to apply the adjustments on the sample image, save a profile and then apply the changes to the other photos on the exact conditions the target image was shot.

The first correction is white balance

But I am afraid I do not know the procedure to apply the other color corrections on free software. But you can apply them directly on Ps, without the need for Lightroom.

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