Jorge 18/8/03 3:44 pm Jorge Parra <photography-at-cantv.net> wrote >Thanks so much for all your responses about my query. > >To make it short, I know of the existence of the Upton's Chromix thing, but >my tiny brain has not been able to start using it. Just don't know where to >start. do the tutorials many ignore them but they are very worthwhile. > >I will be running some tests this week,as I have received the offer from a >printer to make some proofs for my files, and I will be sending both Gretag >Macbeth and IT8 cards, converted form sRGB, ADobe 98 and COlor match, to see >whihc is the optimal output for my system. I will add some "gamut warned" >files and see what happens. if you plan to convert the printer test charts to a destination profile you will have to have a <source profile>, you do not, there isn't one. (see** below)
In any case, what will you do with the charts once you have them back?? Can you measure them - and then what to do with the data? Why not use a reasonably wide gamut testimage like ours (free download on the site), and maybe add your own problem image too. Our image has a spectrum strip so you can se what happens to those really strong colours on the press. You can't properly just convert <from> sRGB, Adobe 98 and Colormatch because you have to have the files in those spaces to start out (but see ** below). Otherwise it's like translating Spanish text to English but using a French>English dictionary. In any case, do remember that converting wide gamut data between workingspaces just clips saturated areas. What [CMYK colourspace] will you convert TO? did the printer give you a profile of his press or proofer? What likely happens at this point is that they probably presume a CMYK type and go from that. Postscript data (which is what they likely deal with normally) doesn't provide for embedded profiles, so don't expect them to read yours. The printing of any RGB files you send may be influenced by how he treats embedded profiles, if he doesn't use them (& many don't ) then you'll find that the most pleasing print will probably come from the RGB nearest to what his system <presumes> pre conversion to CMYK. ** If you are planning to simply assign each of the profiles you mentioned to the printer charts - then convert to a press space/profile, I guess you will perhaps see something useful for visual assesment. It's not a lot different from just desaturating the files a bit though - Assigning a smaller space desaturates, you see. But what will these tests mean in the real world?? Of course whether you use perceptual or relative during the cobversion to the press space will have a BIG effect too. > >THX!. > >Jorge Parra > > >======================================================= >======== >GO TO http://www.prodig.org for ~ GUIDELINES ~ un/SUBSCRIBING ~ ITEMS for SALE Regards, NeilB. Apple Solutions Expert colourmanagement.net :: Consulting in Imaging & Colour Management custom scanner and printer profiles, training on Imacon Scanning supply Gretag + eyeOne, ColorSoloutions basICColor : Display etc. XRite www.colourmanagement.net/ :: www.apple.com/uk/creative/neilbarstow/ =============================================================== GO TO http://www.prodig.org for ~ GUIDELINES ~ un/SUBSCRIBING ~ ITEMS for SALE
