photoshop problem

[Mike Flanagan]

I have a Photoshop question please.

I sent my client a rgb file (flattened), a cartoon....but this is what he says.

When we convert your files to CMYK we end up with a 4 colour black, although
this isn't a major problem from time to time the registration on the
printing presses can wander a bit which could make the text difficult to
read.

I don't want to redo the text, how can I change the original RGB file?
in photoshop.

Thanks,

[jatar_k]

Welcome to WebmasterWorld Mike Flanagan,

I believe it is

Image > Mode > then select CMYK in the list

I have photoshop 7 but I think that has always been the same

[Jon_King]

Changing the original rgb won't help. You will have to make the text 100% K in the converted CMYK file.

All of this is moot if the text is fairly large, say 12 pt and above... the registration won't be a problem - just use it if this is the case.

I will add, that a solid black in litho is often 30% C and 100% K. The added blue makes the black very deep and and rich in appearance.

[batavlada]

I will add to Jon_King post that text (black one) allways must be in K color. And I think that noone print in 100% K. Usually K is about 90% by profile.

Also you must ask for CMYK profile used in printing. There is great number of profiles. In europe is most common Euroscale coated 2. After converting image to CMYK check for colors.

[santrobi]

The best way would be to import your graphic (as CMYK) without the text into a page layout application like InDesign. Then add the text within that program.

However, an easy way to get a solid black in Photoshop is:
Convert your RGB image to CMYK (Image>Mode>CMYK)
Display the "Channels" palette. (Window>Channels)
View each channel separately and erase any unwanted pixels.
If this leaves your text too light, then you may want to redo the text only in the black channel.