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If you like doing your last few color corrections in CMYK so you can see what you are going to get in terms of ink channels --or if you have an obscure need to work in CMYK (like for doing quadtones the right way!) here is a way to use StylusRIP without using StylusRIP (on the 3000, probably other Epson printers as well). After you have done your basic color corrections in RGB convert to CMYK with the appropriate StylusRIP CMYK profile selected in CMYK setup (better yet, make your own CMYK profile or set the CMYK ink colors assignments if you know how to do that). Be sure you convert a copy, not your original RGB document! Now you have a CMYK document that you can tweak (except that StylusRIP doesn't really let you tweak the K channel but go ahead and do it anyway). After you are all set, convert first to Multichannel, then back to RGB. Photoshop 5 will convert your K channel to a spot channel. The RGB colors will look wrong but if you just go ahead and print through the RGB driver (much faster than StylusRIP) with "No Color Correction" selected the colors will print the way you had them in CMYK and the same as if you had printed through StylusRIP from CMYK. The K channel will be integrated into the RGB channels by some miracle formula of the driver (or Photoshop??) but you now have a lot more control over it than just working in RGB. 100% K patches come out a bit weak but 100% CMY blacks come out as full blacks. Lets you put an adjustment curve on the K spot channel to get a last minute tweak of the blacks and shadows. But don't try to correct the second generation RGB colors -- if you still need more color work go back to the original RGB file (before you converted to CMYK) or you can seriously degrade the file. To see how this works, create a CMYK test patch file (one with 100%C, 100%Y, 100%M, and 100% blends of any two to get Blue, Red, and Green). Convert to Multichannel then to RGB. The C will convert to a 255G+255B cyan, the Y to 255R+255G, etc. and the RG and B patches will convert to pure 255 RG&B. Then print through the RGB driver with the "No Color Correction" option and you will see that pure color patches print (no stray colors dithered in). If you create a CMYK document with the Epson StylusRIP profile selected in CMYK setup (or you have the printing inks colors set correctly) the monitor will soft proof how you will print in RGBK. If you start with an RGB file, then convert to CMYK with the correct profile, you can bypass all the RGB profile stuff and get a bit better control in CMYK before you convert back to RGB for the final print. Not near as good as working with a true CMYK RIP but a *lot* faster and you have a better black control than just working with a CMYK preview while in RGB mode. Between the CMYK preview and this final conversion to CMYK and back, you can get a pretty good bit of control out of that old Epson RGB driver! Works especially well if you want to work in CMYK for direct control of quadtone channels or if you are using some really odd ink colors in your Epson (I do odd things with inks you know) and if you know how to set the ink colors in Photoshop. A full CMYK RIP will give you much better control of the total ink and black channel but this procedure does about everything you can get from StylusRIP without the long processing time. For conventional RGB files and conventional ink/paper combinations, staying in RGB with a professionally made RGB profile may very well work better - though you will have limited visualization until Photoshop XX comes up with an RGB version of CMYK preview! Dan Culbertson PS -- When you convert to the RGBK file the K is a *spot* channel -- which means you can not only lay a curve on it to adjust its contrast etc. but you can also click on the channel and change its color from black to (say) a nice deep blue! Nice way to moderate those nasty dead black shadows you sometimes get! But you want to be delicate about it rather than garish (although " garish" does have its fans!). - Please: Stay on topic. Trim quoted messages. http://www.leben.com/lists for list instructions.
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