Leandro Mesias
This helps me know the RGB, Hex, HSV/HSB, & CMYK.
6 people found this review helpful
A Google user
RGB and CMYK are device settings (not colors) and have absolutely no meaning without ICC profiles. This app totally ignores color management and defeats its intended purpose. If you don't get it, Google "the color of toast." Edit 6 Feb 2014: You absolutely CANNOT convert RGB to CMYK (and vice versa) without input AND output ICC profiles! For example, all RGB profiles define neutral grays with equal parts Red, Green, and Blue (e.g. R128, G128, B128). Most CMYK profiles DO NOT define neutral grays with equal parts Cyan, Magenta, and Yellow. GRACoL and SWOP define a neutral middle gray (substrate relative) as C50, M40, Y40, K0. Try converting C50, M40, Y40 K0 to RGB in this app and you will NOT get a neutral gray. You will get an RGB value of R128, G153, B153, which is a blue-green color. This app assumes a neutral CMY value of C50, M50, Y50, which is never the case. If you want to go from RGB to CMYK (and vice versa), you absolutely MUST know the source profile AND the destination profile. Is the RGB profile Adobe RGB, sRGB, Pro Photo RGB? Is the CMYK profile SWOP, GRACoL, FOGRA? Without the CIELAB profile connection space in the ICC profile, you simply cannot convert.
30 people found this review helpful
Sergei Ozerov
February 5, 2014
You can't convert RGB to CMYK exactly, but you can get close. So say you are given a logo in RGB. Color picking the colors and then converting them to CMYK will give you a close match. Using those colors you can create a poster in CMYK and then print it using whatever color profile you have for the printer and so on.