Photoshop CMYK vs RGB?

Question

I have a problem with Photoshop CS6, thing is, I'm practicing on a drawing, or illustration and I set it up on a transparent layer so I can apply it to other surfaces, and the only problem is, I can't save in PNG format unless I put the new file in RGB color model, but I'm afraid this will screw up the colors when I print it on a paper. Will it affect colors in any way or can I just keep working like this?

Answer 1

You can't get CMYK PNG images - png does not support the CMYK colour model.



You should start your drawing in RGB mode and do all of your work in that mode. Converting to CMYK is only needed if you need to save a CMYK TIFF for printing/publishing - it should be the very last thing you do.



Why are you saving your drawing as a PNG? - save it as a PSD. PNG was never designed as a format for printing with - so DON'T use it. You don't need a CMYK image to print on a home printer - in fact in most cases trying to print a CMYK image on a home printer will muck up the colours. CMYK only matters if you are sending to a printer for publication.



If you are printing at home, save your image as an RGB PSD. If you need to share online convert the image to an RGB JPEG - but keep the PSD as your original. Only use PNG if you need to use transparency - otherwise JPEG is the optimal format for the web.



If you are sending the image out to a printers, convert your PSD to a CMYK TIFF (but keep the PSD as the original file) - CMYK TIFFs are the standard format for the printing industry.

Answer 2

PNG (as well as GIF and JPG) is a digital format, not meant for printing. For printing you want to use a native format such as PSD, but when you 'have' to save it as something else for printing use TIFF. Found under "Save As", not "save for web and devices...".



Here's a good little article to help you even further. http://www.dynamicgraphics.com/dgm/Article/28482/index.html

Answer 3

CMYK is flawful - if you type the number 100, it is far different from if you use RGB and then switch to CMYK, even though CMYK shows the same number, 100.



For best accuracy, you should use RGB instead.

Remember, it is RGB, not RYB, because RYB is paint only.



CMYK was supposed to be the official primary color until it had this flaw.

If you are adding color to graphics, you select black in RGB (R:0 G:0 B:0), and you then click CMYK, it says "C:0 M:0 Y:0 K:100."



Black is supposed to be the darkest color, but C:100 M:100 Y:100 K:100 is darker than plain black in CMYK, which is C:0 M:0 Y:0 K:100 (K means black).



PNG, BMP, and SVG are the three best image formats. RGB is superior to CMYK, so you will not have as many problems, but the colors might change a little bit - most likely more vivid.



Therefore, you should save two copies (first time Save, second time Save As) of your image and keep the variation you prefer. If there are no differences, you should generally keep the RGB.



However, CMYK is only a problem on Windows - it might not even affect photoshop.

CMYK is measured from 0 to 100, whereas RGB is measured from 0 to 255.