Damaged Colour Profiles
In this section I will look at what to do about damaged colour profiles.
FIGURE 1 Here we see the undamaged image - exactly what we're expecting to see as we open the file.
An image colour profile can sometimes be damaged and result in one of two sets of warnings being given. Either the ICC profile is seen as invalid, in which case the profile is ignored and a new one will need to be applied, or a more vague message pops up to tell you that the file Info Data cannot be read. In this case a real problem occurs in Photoshop 7-9; although not in Photoshop 6 for some reason. Another warning appears stating that the two profiles are mismatched, even if the working and embedded profile names are identical. To discard and reassign the profile will not solve the problem. Nor will discarding the profile and saving the file, as opening again will give you yet a new warning, before again showing you the other warnings in turn.
Note: Photoshop reads inside profiles to check for mismatches. So even if the names do match it does not mean that the profile information is the same. Either the embedded profile is damaged, or a wrongly named profile has been used.
FIGURE 2 If you ignore the warnings and keep the embedded profile, or convert to the working colour space, then some very strange colour effects can take place, as seen here.
The strange effects that might result will vary depending on which colour profile you assign or convert to. If you only assign a new profile and then save the image, it can still be rescued. But converting the profile will change the numbers in the pixels, so that the colours you see on the monitor will then be locked into the file with no chance of rescuing the image. To correct the problem requires saving the image in an older format that does not hold colour profiles.
How to fix the colour profile:
- Open the image with the damaged profile.
- Select the 'Discard Profile...' option.
- Save in a format such as BMP.
- Close the file.
- Open the newly saved image.
- Assign the correct profile.
- Resave in preferred format.
Two extra important points:
• Older file formats, such as BMP, usually do not hold image metadata either. If this metadata is important, then save the File Info data into a spreadsheet first, so that it can be imported back into the corrected image later.
• If the image is a 16-bit file then use the Photoshop RAW format to correct the profile problem. However, this requires more work as all file header information is then removed.