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frantz · #1 (**permalink**) 04-19-2006, 05:58 AM

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? :wink:

Bart · #2 (**permalink**) 04-19-2006, 06:04 AM

Quote:

Originally Posted by frantz

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?

Check that resolution/image size are the same for both versions?

frantz · #3 (**permalink**) 04-19-2006, 06:07 AM

Yes, 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? ?????

I have no idea?

Jezza · #4 (**permalink**) 04-19-2006, 06:16 AM

I just tried it over here and couldn't replicate it. Are you certain that the two documents are indentical in every way?

Image size, resolution, profiles.

How are you measureing the 90% difference?

frantz · #5 (**permalink**) 04-19-2006, 06:34 AM

Yes, both documents are indentical in every way (Image size, resolution, profiles.) ? I made the black and white from the orig cmyk color image.

I am measuring the 10% difference with the eye dropper tool. The image is of a womans head and I have the eyedropper in her hairline. When I am in the black channel I see it at 91% and when I view as 4/c cmyk it is now 81%?

Thank you so much for your time. I really appreciate it.

Jezza · #6 (**permalink**) 04-19-2006, 06:44 AM

Quote:

Originally Posted by frantz

Yes, both documents are indentical in every way (Image size, resolution, profiles.) ? I made the black and white from the orig cmyk color image.

I think that may be your problem, once you have selected the image and before you paste anything into the black chanel, make a completly new document.

In the new document dialog box there is a drop down menu, called preset, if you have the original document open, scroll down to the bottom of the list and it will be listed as a preset, choose that. make sure the new doc is in cmyk mode and tehn paste into the black chanel

Hopefully that'll fix it

frantz · #7 (**permalink**) 04-19-2006, 06:51 AM

Hello,

OK I have it open and went to create a new document and have "Preset Size" as an option and that is all? I am using Photoshop 7.0. Is that why?

Thanks again for you time. I really appreciate it.

Jezza · #8 (**permalink**) 04-19-2006, 06:55 AM

Quote:

Originally Posted by frantz

I am using Photoshop 7.0. Is that why?

Don't know about that frantz, I was using CS 2,

The point is to make a completely new document not use the one you opened originaly. If I have read you correctly

I'm sure one of my lads had a similar problem last year with a DCS2. I just asked him and he can't remember how we fixed it, having said that neither can I :roll:

Anyone out there PS 7 that could have a look at this?

frantz · #9 (**permalink**) 04-19-2006, 07:00 AM

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. It only took me 4 hours to figure this one out...YIKES

Jezza · #10 (**permalink**) 04-19-2006, 07:04 AM

Nice work frantz, now we all know