This one will not die, not from: image → mode → CMYK color. It's that simple, but do you really understand the mystery? The facts are not as simple as we imagined, and there is a lot of emphasis on the conversion of color patterns.
Here is an example to illustrate:
The first picture is the original inside PS2
1) You open the Edit in the PS → Color Settings select “North American General Purpose 2†and confirm. Open an RGB image and convert it to CMYK.
2) Then change the color mode: "Japan's regular use 2", confirm, and then open the original RGB map, convert to CMYK mode and save it.
3) Open the two converted CMYK pictures. At this time, the picture you see is almost the same color. Yes, it's not much different from a four-color display, but when you open the information panel and measure two color values ​​in the same location, you will find that their values ​​are different.
Contrast the various color versions for your reference.
This shows that: using different color settings from RGB to CMYK is not the same color, which is directly related to the color performance and level of your printed products. This introduces a concept of color separation: long black version, short black version (in fact, we have been doing color separation work from RGB to CMYK, the output company is only to export your favorite files into film And it can be understood that it is almost like you are printing.
What is the long, short black version? Simply say that the long black version is the black version from 10% to 15% began to appear, and the short black version is from 25% to 30% only began to appear (due to different image tone). The difference between the two is that the black version of the short black version is mainly concentrated in the dark portion, and the black portion of the intermediate tone is formed by overlapping with the CMY; the long black version is formed by the appearance of black and the CMY color from the middle portion. Relatively less. Performance in four-color prints is the length and length of the black version of the entire picture will be different.