PDF Color Space Inspector

Exactly where the RGB is. Documents are frequently mostly CMYK with a handful of RGB images or RGB-specified vector elements that were never converted. This report separates colour space by usage, so you can see whether the problem is the whole document or three placed images, which is the difference between re-exporting and fixing three links.

It is an embedded ICC profile plus an identifier declaring the printing condition the file was prepared for — a coated stock under a particular standard, for instance. It does not change any colour values; it records the assumption under which they were chosen, so a press can reproduce them faithfully or convert them knowingly. For commercial print, yes. For screen or office printing, no.

A Separation colour space names a single ink printed on its own plate — a specific brand-book colour, a metallic, a varnish. Each one is an extra plate and an extra cost, which is why an unintentional spot colour matters. Every separation carries an alternate space and a tint transform so a reader that cannot print the real ink can approximate it on screen.

Because a monitor emits light and paper reflects it, and the achievable ranges genuinely differ. Saturated RGB blues and greens have no CMYK equivalent and must be mapped inward to something printable. That mapping is what colour management exists to make predictable: an ICC profile and an output intent turn an unpredictable conversion into a documented one.

Often not, and this is a real cost. A document that looks black and white may specify its blacks in CMYK or RGB, in which case a press may run all four plates to print what should be one. This report shows the declared space rather than the appearance, which is how that gets caught before it is billed as four-colour.