Questions about color conversion of single process colors with Fiery

[NefariousDrO]

It's been a few years since I've dealt with a Fiery RIP for a digital machine, but I seem to recall there's an option either buried in the print command or possibly on the RIP itself that lets you specify using your own color separation-values. When I needed to do that I had to print separations to the RIP, with a setting that said "combine separations" enabled.

[Possum]

If you are using Command Work Station, there is a setting under the Color tab that says Combine Separations.

As far as your grayscale tints, it sounds to me as though the RIP is trying to emulate the appearance the file wants rather than actually using the info in the file. Like it thinks 25% black looks more like 25% black if it uses CMYK. If you don't have the outboard Fiery, it doesn't print halftones, and this is what it may be trying to accomplish.