HOWTO: Colour Calibrate With QPcard 201 and LPROF

This howto is incomplete and untested (but might work, though).

In a related howto I described how to use the ICC profiles that come with Canon Digital SLR (EOS) together with UFRaw to digitally develop colour calibrated photographs. This howto will describe how you can use the QPcard 201 and LPROF to create your own ICC profile that describes the lighting conditions of a photo session. This profile can then be used to further correct the colour of you pictures.

You will need:

See also:

  1. Download the target reference data file for the QPcard 201, qpcard201.it8, and put it in your folder for such files, tentatively at ~/.lprof/target_refs/.
  2. Dowload the corresponding template file, qpcard201.itx, and put it in the folder for template files, tentatively at ~/.lprof/templates/.
  3. Open LPROF and go to Preferences -> Install Reference File.
  4. Select the correct IT8 Target. You might have to select the correct folder where you put the IT8 file, the suggested location being ~/.lprof/target_refs/.
  5. Select the correct template, which should be available in the drop down list if you put the file in the correct location. After this press Ok and Done.
  6. Before photographing in a certain setting or lighting condition take one picture with the reference card (QPcard 201) at the position where the motive will be. Make sure that you have manual white balance.
  7. Take all the pictures you want in the same setting with the same white balance. If you change setting or lighting conditions, you will have to take a new picture of the reference card.
  8. Use UFRaw to convert all your pictures, including that of the reference card, with the same white balance setting and to the same colour space of your liking. I suggest using a large colour space and 16 bits colour depth.
  9. In LPROF, select Camera/Scanner Profiler, load the picture of the reference card and select the QPcard 201 target.
  10. Create the ICC profile. How I don't know, because LPROF keeps crashing for me at this point.
  11. Load your pictures into Cinepaint
  12. Use Cinepaint to apply your colour profile to the picture.
  13. All done! The new colour profile describes the mapping between the picture's RGB values and real colours.
  14. Send me an email describing how it went. Use the "contact" form on my main page.