LibTiff Mailing List
TIFF and LibTiff Mailing List Archive
March 2002
Previous Thread
Next Thread
Previous by Thread
Next by Thread
Previous by Date
Next by Date
Contact
The TIFF Mailing List Homepage
This list is run by Frank Warmerdam
Archive maintained by AWare Systems
Thread
2002.03.05 20:58 "Re: Photoshop Alpha Channel", by Chris Cox
At 2:53 PM +0000 3/5/02, Hulme, Phil wrote: > Hello All, > I'm looking for some help with adding a grayscale TIFF to a CMYK > tiff as a photoshop alpha channel. I know that Photoshop does not mark these > in strictly the correct way. Can any one suggest how I can achieve this? What do you mean "not mark these in strictly the correct way"? Photoshop writes the transparency channel as type 1 (associated), and additional channels get marked as type 0 (unspecified) because we don't know how the user intends to use them. Any additional, non-associated channels you put in the TIFF file will be read as alpha channels by Photoshop. Only one associated channel will be read by Photoshop, as transparency. Chris