CMYK or RGB?

[robert_davis7]

Hi, simple question (but for some reason, I couldn't find it in the

archives). I have a printer with CMYK cartridges. Should I be

converting my photos to CMYK in photoshop before printing them? I've

had good results in RGB, but I wonder if it would be better to convert

before printing. Thanks in advance!

 

(I'm using Photoshop CS, a PowerMac G5 and a Canon S-600 printer)

[mystuff]

no, leave your images in rgb

 

consumer-oriented printers have drivers that expect rgb images and are optimised for that format

 

if you convert to cmyk it is also likely that the colours will shift or be clipped (depending on how you do the conversion) due to gamut differences

[goldenhour]

You don't actually have to convert the file permanently to CMYK, but if you View>Proof Setup you can do a temporary conversion, and use that to print. This has two main benefits:

1: You have control over how the conversion takes place, whereas if you let the printer do it for you, you don't know exactly how it is converting.

2: You can preview the image using the conversion that will be sent to the printer, which will give you a rough idea of what colors will be clipped (and some WILL be clipped) in the conversion.

 

I would reccommend finding a paper profile for the paper you are using, you can find some here: http://www.photoexpert.epson.co.uk/UK/PRODUCTS/icc_download.htm

 

Full info on the exact steps to follow when converting and printing can be found here:

 

http://www.drycreekphoto.com/Frontier/using_printer_profiles.htm

 

If nothing else, I would recommend learning about color profiles in general and how they work, your results will be more predictible if you use profiles!

[link]

Don't convert to cmyk. Forgetaboutit.

 

Your printer software does the cmyk conversion and has been optimized for the

canon inks and papers.

 

To use cmyk in photoshop you must have control over each ink individually in the

printer and this requires expensive software called a Raster Image Processor (RIP).

 

Send the printer rgb and be happy!

[goldenhour]

I still insist that at the very least use view>proof setup in Photoshop to get a rough idea of what the file will look like when it prints, and it helps very much to find a paper profile for the paper you are using, that way you can get an even better idea of what's going to happen when you print, even if you don't use proof setup to print (I can't image why you'd rather trust the printer's canned software over your own control, but so be it...)

 

If nothing else, use command-Y to preview CMYK mode and you'll be surprised what's happening to your files in conversion.

[Jochen_S]

If you ever convert to CMYK be careful and decide what you are doing it for. Think carefully about dotgain. Inkjets have maybe none, offsetpresses have a lot of.