Ditto on this one!
A Total Area Coverage display for CMYK-images, with Spot Colors factored in if possible, would seem quite useful in Photoshop.
This is also relevant to my interests.
Yes this is a fair enough Feature Request. But there is already a way to do this of course: Using a Threshold Adjustment, and Eyedropper points set to Total Ink, its pretty easy to see a graphic overlay of areas that are out of any ink limit. By adjusting the blending options of this Threshold Adjustment you can create a kind of "Ink Limit Quick Mask". The whole thing can be automated.
Does the VIEW > GAMUT WARNING preview not also factor in or correlate
to total ink for a given profile?
No, it does not (as far as I can tell).
It is useful to assess which regions in an RGB- or Lab-image are out
of gamut for a certain CMYK-space, but within a CMYK-space itself it
does not help.
Yes as C. says, Gamut Warning is mainly for while you are working in RGB, assessing what colors are out of the CMYK Gamut. Colors that will make the CMYK conversion a little more problematic.
Usually SOME areas out if gamut color are not problem. Because of clever rendering intents in Photoshop like "Perceptual". But huge areas massively out of CMYK gamut, if you are retouching for print are likely to create problems on conversion. Thats actually one of the reasons why sRGB is chosen as the default space for Photoshop: because most people working for print are completely unaware of these issues. But its a low-gamut working space. Adobe RGB and ProPhoto RGB are more likely to create gamut issues, so you really should know what you are doing …
Using Proof as CMYK (Command Y) will also demo whether there is banding and problems after conversion. Gamut Warning is helpfully Command > Shift > Y. So no excuse for retouching dodgy over-saturated, out of gamut RGB colors in these spaces.
Yeah, GAMUT WARNING was a big part of my workflow since I had to
routinely make judgements on my newsprint ads that I repurposed for
different media/mediums (from RGB original, of course). Does the
original poster mean functionality like Acrobat Pro > Advanced > Print
Production > Output Preview > Total Area Coverage preview?
Terry : yes, I mean functionality like Acrobat Pro > Advanced > Print Production > Output Preview > Total Area Coverage preview (or InDesign "Ink Limit" view option in the Separations Preview palette).
Since most of the photos I work with are CMYK, I don't think the Gamut warning can be useful in my case. The Threshold Adjustment suggestion is a valid one, but it looks more complicated than just entering a maximum ink density (like 280% or 300%) in a field and seeing right away which parts of the image are over that limit.