How do I determine the black generation settings and dot gain in an ICC profile?
A. Some profile software vendors add a private tag which includes the black generation parameters used in making the profile. To estimate the values for yourself, make a neutral ‘ramp’ containing a grayscale in CIELAB colour space, from 0-100 in L* and keeping the a* and b* values all to zero. Transform this using your output profile, using the relative colorimetric intent. The maximum and minimum values of K will give you the black start and black max respectively; while the sum of the C, M, Y K values for the L*=0 colour will give you the maximum overprint (or TAC) value. (Note that in real images there are rarely pixels with an L* of zero, so the effective TAC is likely to be lower.) The ratio of K to C in the midpoint of the ramp will indicate the relative amount of GCR used, while the ratio of C to M and Y will indicate the gray balance. You cannot usually tell the amount of dot gain in the printing process from the profile. If the measurements of the test chart used to make the p
Related Questions
- With all things being equal, is there any reason to see an increase in black dot gain simply by changing the print sequence from CMYK to KCMY?
- When using an ICC printer profile with Adobe Photoshop what settings are recommended to reduce the reddish cast from my image?
- How do I determine the black generation settings and dot gain in an ICC profile?
