For one thing,.. you may need more density in the deepest shadow. If there’s any black detail, it could go to 3,3,3 (and even more). …. but it should make sense, if you convert to a CMYK profile, due to Total Ink limitations of the offset process, for the darkest shadows to look somewhat light on the screen (and even in print) because they are not as dark as they could be if you’d print one color at one time (for instance).
The ideal Black on press would have 100% of all inks.
The real Black has between 230 (often) and 340% (seldom). A lot of times, converting to the CMYK profile, you get less ink in the shadow than the press can use. Add some black in the darkest shadow with a curve, especially if the blackest areas are not vast (under half a square inch).
Keep track of the amount of black added, for future reference.
Theoretically, if the RGB image was entirely in-gamut, the softproof should not show any difference right?
If these are Photoshop-generated black shadows, the resulting separations would depend on the CMYK profile that you are using and the settings for ink limits and Black generation.
….and regardless of what those CMYK number are they should still appear like the RGB image.
I wonder if a bad monitor profile could be involved here.
Peter beat me to it. Doesn’t matter how great the monitor is if it hasn’t been calibrated to the current room setting. Values will drift over time, so calibration has to be redone very regularly. And apparent contrast can change depending upon the current ambient light levels.
Neil