Help - Removing the K from CMYK

dinners

dinners

In Memoriam
Messages
15,745
Name
Phil
Edit My Images
Yes
Hi there

I've been asked to do the following - just wondered if anybody can advise on the best way of removing the black and retaining just cyan, magenta and yellow. For what it's worth I've got Photoshop 7 and Corel Paintshop Photo Pro X3

I need the file converted into CMYK and then the K element removed so that I can print just the CMY onto prejector film which I then stick to the rear of my lithophane to hopefully give me a colour lithophane
 
Can you.... ?
Convert to CYMK
Split channels to CYMK (4 images)
Delete K (Black) channel
Combine the 3 remaining channels?
 
That's about where I am now.

I've split to CYMK - got 4 (what appear to be) black and white images..........
 
They're black and white images Phil until you combine the channels again, when the combined image reverts to colour

You may need to adjust levels a bit with the black channel missing.
 
OK

Doing it in Photoshop now.

I've converted the RGB to CMYK so on the right hand side I now see 4 channels (where I normally see Layers)

1 = CMYK
2 = Cyan
3 = Magenta
4 = Yellow
5 = Black

I can switch visibility off for all but the C, M & Y but now I'm unsure how to combine just these 3 chanels to make a new file.

I was looking for a 'merge visible' type option like you get with levels.....
 
dinners said:
OK

Doing it in Photoshop now.

I've converted the RGB to CMYK so on the right hand side I now see 4 channels (where I normally see Layers)

1 = CMYK
2 = Cyan
3 = Magenta
4 = Yellow
5 = Black

I can switch visibility off for all but the C, M & Y but now I'm unsure how to combine just these 3 chanels to make a new file.

I was looking for a 'merge visible' type option like you get with levels.....
Click to expand...

if you right click the black channel it give the option to duplicate or delete that channel. Just delete then save as either .psd, .eps or .raw and you will have a file with only CMY
 
I use an old version of PSP . 'Combine Channels ' is on the same drop-down menu as 'Split To Channels'

If you delete the K channel it can only combine the remaining three channels. The original CYMK image shouldn't be combined anyway, but delete it and it can only combine the three remaining channels.
 
Thanks folks

Channel mixer was the only tool I could find but that only seemed to allow me to adjust channels not combine them.

I've been able to remove the K channel by deleting it but unable to somehow combine the 3 remaining channels to create a .jpg

I've saved the file as a .psd which now just contains CMY but the person who sent me the file to split did so because they don't have Photoshop. They do have Elements though.
 
Thanks Paul

I managed to email the psd file in the end with the 3 channels seperated - I never figured out how to merge them together again.
 
You don't need to split the channels to delete the black just open the channels palette and right click on the black (K) and delete. This leaves you with the CMY channels.

6381761569_792419891b.jpg
 
Cheers Wayne

I think that's what I did.

The file that I was given was RGB in Jpg format
I changed it to CMYK
Opened the channels, deleted the K

This left me with a psd photoshop file containing just CMY

The problem I found (although I just sent them the psd file in the end) was then getting the file back to a jpg.
 
It needs to be RGB to save to jpeg.
 
Splog said:
It needs to be RGB to save to jpeg.
Click to expand...

You can save a cmyk jpeg no problem.

You won't be able to save the file as a jpeg once you have removed the k channel because it's now classed as a multichannel file type and no longer cmyk.
 
Thanks guys.

Turned out the psd file was fine and I learned something new which is always a plus.
 
You must log in or register to reply here.
Back
Top