Hi Jason,
You need a special "cow" profile; these can be obtained at your local university extension service. Alright, not really. You've received some intelligent comments. What I would say is similar: You have two distinct but overlapping issues: One is the calibration of the press, which is a simple 1D curve adjustment that can lighten and gray-balance results, and the other is that images should, ideally, be optimized for the specific output condition, even though the press is calibrated. If the images are already printing well on coated stock they can be converted, separately in Photoshop, or in situ in a PDF using, yes, Callas PDF Toolbox, or its OEM little brother in the Convert Colors tool Acrobat's preflighting, or an industrial-strength color server such as ColorLogic ZePrA, which handles a huge variety of color management tasks with a high degree of automation (Disclosure: I sell this stuff). The critical point in my view is that a different print condition may involve more than just a darkening of single colors but changes in overprinting behavior as well, and to extract the best possible results it's a good idea to have that calibrated press/paper/screening combination characterized in the form of an ICC profile (off-the-shelf or custom) and convert your jobs though a device link employing that profile as its destination, in suitable software. This way you can safely convert vector objects as well.
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Mike Strickler
MSP Graphic Services
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