problem in coverting black color to black channel only

[2mira]

i try to convert black color in any file to black channel in this method:
From photoshop
Edit menue - convert to profile - custom cmyk - maximum - black ink 100 - total ink 300
this method worked perfectly in photoshop
and i see black color in black channel only

the problem is:
when i convert psd file to pdf
from adobe advanced menue - print production - output preview
black color appear in four channel
i need to know how to solove this problem

 

[Stephen Marsh]

This problem is “by design” :] (yes I know, don’t shoot the messenger)

There is probably a 90%+ chance that your file is actually K only and not CMYK.

Let me guess, your image and or PDF has an ICC profile embedded in it for this image? Also, Acrobat Pro output preview has a different “simulation profile” selected at the top drop down menu in separations preview than what is in the PDF for this image? I am also guessing that you are not using a PDF/X standard?

What happens if you make the simulation profile exactly the same as the profile in the image? Is it now correct?


Stephen Marsh

 

[2mira]

screen shot for my question

screen shot for my question

This problem is “by design” :] (yes I know, don’t shoot the messenger)

There is probably a 90%+ chance that your file is actually K only and not CMYK.

Let me guess, your image and or PDF has an ICC profile embedded in it for this image? Also, Acrobat Pro output preview has a different “simulation profile” selected at the top drop down menu in separations preview than what is in the PDF for this image? I am also guessing that you are not using a PDF/X standard?

What happens if you make the simulation profile exactly the same as the profile in the image? Is it now correct?


Stephen Marsh

THANK YOU for reply
I take screenshot for file in photoshop and the same file in acrobat pro
I hope it will help

 

[Stephen Marsh]

The screen captures are too small to see.

Can you attach the PDF (or a crop)?

Test again by saving the file from Photoshop with *no* ICC profile. Does Acrobat then show this correctly?


Stephen Marsh

 

[2mira]

Sorry for that

Sorry for that

The screen captures are too small to see.

Can you attach the PDF (or a crop)?

Test again by saving the file from Photoshop with *no* ICC profile. Does Acrobat then show this correctly?


Stephen Marsh

Try this link
View image: Screen shot 2015 03 04 at 11 00 30 AM
View image: Screen shot 2015 03 04 at 10 59 18 AM

 

[Stephen Marsh]

The output preview simulation profile is: U.S. Web Coated SWOP

The Photoshop file is using the old legacy Custom CMYK engine (a different profile).

If you assign the U.S. Web Coated SWOP profile to the Photoshop file, you should see black only in Acrobat Pro Output Preview.

If you remove the profile/don’t colour manage the Photoshop file, you should see black only in Acrobat Pro Output Preview.

If you change nothing in your Photoshop file and then simply change the profile in the Output Preview in Acrobat Pro to the same as the Photoshop file, you should see black only in Acrobat Pro Output Preview.

I’ll save the “why” for later :]


Stephen Marsh

 

[2mira]

The output preview simulation profile is: U.S. Web Coated SWOP

The Photoshop file is using the old legacy Custom CMYK engine (a different profile).

If you assign the U.S. Web Coated SWOP profile to the Photoshop file, you should see black only in Acrobat Pro Output Preview.

If you remove the profile/don’t colour manage the Photoshop file, you should see black only in Acrobat Pro Output Preview.

If you change nothing in your Photoshop file and then simply change the profile in the Output Preview in Acrobat Pro to the same as the Photoshop file, you should see black only in Acrobat Pro Output Preview.

I’ll save the “why” for later :]


Stephen Marsh

I used - custom cmyk in photoshop to put black color in black channel only
this way i knew from printplanet site and i find it easy way
i need to know how to remove black from other channel both in photoshop and acrobate pro
because files sent to print in pdf format
if you know the solution
would you please send screenshot
THANK YOU

 

[Stephen Marsh]

To remove values from the C, M or Y channels in Photoshop, target the channel in question and then fill with white or apply and curve and pull the shadow 100% to 0% (zero) making the curve a straight horizontal line.

Once you are sure that the Photoshop file only has data in the K channel, when you save you can chose to:

* Assign the U.S. Web Coated SWOP profile to the Photoshop file so that it matches the default profile in Acrobat Pro Output Preview Simulation Profile.

* Remove the profile/don’t colour manage the Photoshop file - save with no ICC profile embedded/tagged.

* In the Acrobat Pro Output Preview set the Simulation Profile to match the profile used in the Photoshop file.

HINT: There probably is no CMY in the file, as the source profile and the simulation profile are different - Acrobat Pro Output Preview Separations are indicating the *potential* for a colour conversion that would introduce CMY where there currently is no CMY. :]


Stephen Marsh

 

[2mira]

GREAAAAAAAT THANK YOI