Convert Grayscale image to CMYK Black Only????

[FrantzLitho]

I have a 4/c image that I want to convert to a CMYK image with the image in the black channel only. (I do not want it to convert to a CMYK Black image). In the real old photoshop I think you used to go into Separation Setup and set to Maximum. If I copy the grayscale image and make a new CMYK document in photoshop and paste into the Black channel only then it is at 90% of the original image?

Any ideas?

 

[blueark]

That's strange... just tried pasting a grayscale image into the black channel only and it worked fine. I presume you've checked the other channels to see if they're still empty? If you fill a grayscale image with 100% black, does it still come in at 90% when you paste it? Maybe there's some weird color management / proofing thing going on...

 

[jimoblak]

a CMYK image with the image in the black channel only

That would be a one channel grayscale image. Correct?

It would be inefficient to have the C, M, Y channels empty but still saved in the image file. Why would you retain those channels?

 

[FrantzLitho]

GOT IT !!!! GOT IT!!!!!!

Open up grayscale image.
Go to Image > Mode > Convert to Profile

Destination Space > Custom CMYK

Black Generation > Maximum

This will change doc mode to CMYK and put into black channel only.

Thanks for your help!!!!!

 

[dmacster]

I'm with jimoblak - why have three empty channels? Inquiring minds and all that...

Donna

 

[FrantzLitho]

Because I need to customer wants part of the image Black Only and a small area on the persons face 4c.

 

[dmacster]

Oooh...

 

[Foamcow]

You could also create a channel mixer adjustment layer and apply a mask to it to allow the colour image to show through in particular areas.

<honk>*:O)</honk>
Foamcow Heavy Industries - Web site design in Cheltenham and Gloucester
Ham and Jam - British & Commonwealth forces mod for Half Life 2