PThompson wrote: > As my business is supplying RGB files to agencies I know nothing of CMYK > which has been OK up till about 6 hours ago. However, today I have been asked > to supply an art gallery with prints. snip > I only seem to get to speak to someone (the owner!) who doesn't seem to be > able to tell me much except "provide CMYK files".
OK, the easy way is to find another printer (try Touch Digital in London or Matthew Ward in Newcastle [I think] - both print an a 9600 on RAG paper, I've CC'd them) who are colour Management savvy. If not you could be in for an exercise in futility. The best option I can suggest (given that you want to stay with that print shop or can't find a CM savvy one) is to have the Print shop print a printer profiling target like an IT8. Then have someone create a CMYK profile for the paper. This will allow you to convert to the "right" CMYK. Just make sure the print shop guy doesn't tweak his machine from time to time. If he runs a well calibrated (as opposed to profiled) workflow it should be without major problems. > I have "converted" the RGB's to CMYK in PS7. They lose a lot of the vivid > colours straight off. Any CMYK will, as it's a smaller colour space. The water is wet, deal with it... >Pouring over Martin Evening's book I have learned about > Relative Colorimetric and Perceptual, with and without black point > compensation. Generally the images look better with RC + black point. It will look more saturated yes. But without an accurate CMYK target for this guy you have between little to no chance of getting your prints right. With a profile you can simulate on you (calibrated) screen what the Print will look like, and hit it within a few %... > > So now to the Colour Settings. Under Colour Spaces > CMYK I don't know if I > should tick Euroscale uncoated v2 or coated V2 (or any of the others)? I doubt anyone can be of help here. > I am going to have them do three small A5 tests on Somerset Bright White > Watercolour, Cotton Canvas and Matt Paper. Go for a profile target instead. It can be as small as A4... > > I asked him what ppi I should supply. He said "it depends". It means he doesn't know which DPI will yield optimal results on his printer... > So I volunteered > helpfully 300? He said that's a good average! So I presume I should go for > that? Ask what kind of printer he uses. With that info we can perhaps offer qualified help. > > I haven't had any prints done before so don't know how much sharpening should > be done. I'll be doing 21inch x 7inch landscape panoramics. USM is a complicated on. If you want the easy way out, but NIC Sharpener Pro. In this you need to specify the output size and printer type, and the application will give a really good estimation. Other than that it takes time and experience (which is somewhat more expensive than the application). There is no one set formula, it depends on image content, size of original vs. size of output and it depends greatly on the output media. > Martin Evening's > book says that often it's not what it looks like on the screen but experience > that counts on this. Agreed. The screen in 100% is the only thing you can really rely on. If you make it appear a bit too sharp on screen it will look good on print. But the exact amount depends on a bunch of other factors. > Er, my experience is nil, I know "it depends" but I'd > sure like a ball park figure to start me off. Buy NIC Sharpener Pro! > I have read USM 200/ 1.5/ 0 on > smaller images for the web but what about large prints? The above numbers will probably give you a wide halo around dark edged which will look ridiculous on screen. The Radius is much too wide in my experience. Amount could be anything, and threshold should often be more than 0 (but less than 5). > > I realise that converting to CMYK is not simply a matter of ticking these > various menu pull downs but it's all I have time for right now, so any advice > anyone could put forward; to at least give these tests a fighting chance > would be very useful indeed. If you have the bloke print a profiling target you could have a accurate printer profile within 2-3 days. If you don't you could struggle for weeks... If you use a printer that are CM savvy you could have final prints within a day or two in the UK. Don't torture yourself, life is too short. Best Regards Thomas Holm / Pixl ApS - Photographer & Colour Management Expert - Adobe Certified Training Provider in Photoshop� - Imacon Authorized Scanner Training Facility - Remote Profiling Service (Output ICC profiles) - Seminars speaker and tutor on CM and Digital Imaging etc. - Home Page: www.pixl.dk � Email: th[AT]pixl.dk -- =============================================================== GO TO http://www.prodig.org for ~ GUIDELINES ~ un/SUBSCRIBING ~ ITEMS for SALE
