On 12 Dec 2014, at 23:08, Steve Upton <upton@chromix.com> wrote:
By generically I mean that there are certainly CMYK printing systems that will happily accept inking levels up to 400% without any issues so Photoshop needs to take those into consideration as well. While you may consider a TAC level part of the gamut boundary, I don’t think that I would. Or at least, I would not consider it part of the device gamut boundary. It could be argued that it should be considered part of the profile’s rendered gamut boundary.
As an image maker, that’s precisely what I’m arguing. I’d consider any CMYK values that can’t be “round-tripped” back through a CMYK profile to form a gamut boundary which will clearly highlight TAC issues. -- Martin Orpen Idea Digital Imaging Ltd