The advantage of using Adobe RGB or ProPhoto RGB is that the larger colorspace allows more editing capability without clipping, preserving the integrity of the image data. With sRGB, you can rapidly lose data in doing simple curves and other tonal manipulations. These losses add up in successive edits. For the greatest possible editing flexibility, set your RAW output quantization to [EMAIL PROTECTED] and ProPhoto RGB colorspace.
Printers and screens don't have that much gamut to work with so a translation must be made to the appropriate colorspace for those output devices. Photoshop uses the monitor profile to translate from the colorspace of the data to the screen for editing purposes. You can see clipping when it occurs as you edit in the histogram, not on the screen. When you print, to obtain the truest match to what you see on your screen with Photoshop you must print using a color managed workflow. You tell Photoshop to drive the printer and control color management, pick the correct match in Paper/Ink profiles for your specific printer model, inkset and paper, and Photoshop will translate the image data to that output device using the intent you specify. The intents that work best for photographic work are Perceptual or Relative Colormetric: they produce the least amount of data loss and the closest match to the screen rendering. The only way to know how they differ with a given image, far as I am concerned, is to test print using each of them and see how the translation works for that image. In this printing workflow, you must also have the ability to turn OFF the color management at the printer driver level otherwise you will be translating the color metrics twice with unpredictable results. If your printer driver does not support turning off color management, the best results I've seen are to do a colorspace conversion to sRGB and then 16bit to 8bit reduction up front, to most closely simulate what the output device will image the data as, and then print using the "Let Printer Manage colors" so that the printer driver is accepting a known baseline color gamut in the data you're sending it. You can then use the driver's controls to manipulate the output rendering to your taste. I find the color managed print workflow to be much more consistent and repeatable, presuming good monitor calibration/profiling, proper set up of Photoshop's color management settings, and good quality paper/ink profiles for a given printer and inkset. However, the bottom line in print quality is always dependent upon what works best for the equipment and configuration for you ... Once you come to a setup and workflow that works, you save yourself a lot of headaches and waste by standardizing on it and working with it, regardless of theoretical considerations. Godfrey On Mar 9, 2007, at 6:59 AM, Markus Maurer wrote: > Indeed sRGB seems to be the easiest way, if I change Photoshop to > Adobe RGB > or PhotoProRGB I get these washed out JPG savings no matter if I > choose > SFW or save as --> JPG. I wonder how much information gets lost in > press > print with sRGB, the tutorial I saw on the web is quite impressive > and show > a > huge loss in color space with sRGB compared to Adobe RGB or even > better > PhotoProRGB. > > Has somebody with a high end printer ever tried the different color > spaces > on a printer, I wonder if I really have to choose PhotoProRGB for my > calendar project to get rich and deep colors as promised > > Have a look at: > http://www.luminous-landscape.com/tutorials/prophoto-rgb.shtml > . > But when I can't see all the colors on the monitor for proofing I'm > a bit > afraid of getting color cast and unprintable colors later as a nasty > surprise. > Decisions, decisions, I want more time to t a k e photographs > instead ;-) > >> >> When I worked in a lab using a Fuji processor, adobe RGB gave me a >> terrible >> blue cast. Switching to sRGB fixed the problem. This was with >> the IstD >> >>> ..Experimenting with Adobe RGB, sRGB and ProPhotoRGB color space >>> settings >>> leaves me confused enough for today. Too much reading.... >>> I will have to go out tomorrow for some close-ups, that little >>> 18-55mm Kit >>> lens will come handy for some first landscape test shots. >>> >>> http://www.mypage.bluewin.ch/solicom/leoleu1.jpg > -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net

