on 31/1/03 5:42 pm, Shangara Singh at [EMAIL PROTECTED] wrote: > On 31/1/03 4:40 pm, Dominic Blackmore wrote: > >> If an RGB file is opened 'do not color manage' in PS and then the colour >> mode is change to CMYK does PS use the working RGB space to as a starting >> point for the conversion? > > It displays the file in your RGB working space so it's a fair guess that's > where it will start from. > > You could, I suppose, test the theory by duping the file and assigning your > RGB working space to one and then converting both and see if there's any > difference.
Dear Shangara & List, Following your suggestion I have converted the two files and got the same result (visually and 'by the numbers'!) in CMYK. The reason I posted the question was that a Repro company has told me that they would prefer me to supply a job in RGB so they can do the conversions but I would prefer to try out my new profiled 7600 and Best Photo Xposure RIP to supply CMYK targeted files and proofs. We have agreed to do a test where we both start with the same file and both supply a converted file and matchprint to a given standard. The problem I have is that I suspect a 'closed loop' situation and the guy has already told me he discards the tags upon opening tiffs (just works 'by the numbers'?!?); hence the 'not colour managed' bit of my original post, I have asked him if his production dept. has a standard RGB working space, If they have I fear it could be sRGB. So, I do my Adobe RGB to whatever CMYK conversion using the same CMM and intents as he has on his system and he opens my Adobe RGB file not colour managed into an sRGB workspace and converts to whatever CMYK from the wrong starting point as I have just tested. Result............ different result! It doesn't matter if my Epson is as accurate as his Sherpa or Digital Cromalin (contract vs. creative proofing is another story). Our Matchprints won't match and in his mind he will have a justified reason to reject my files! aaaarrrrrggggggg. OK, I know if I can find out what his starting point is (working RGB space) it would be fair(er) test but we can't all be expected to second guess whats going to happen to our files once the job has left our control. Rant over (off to find a beer!) -- Dominic Blackmore Photographer =============================================================== GO TO http://www.prodig.org for ~ GUIDELINES ~ un/SUBSCRIBING ~ ITEMS for SALE
