Modifying registration black in a Photoshop Image

[DigitalCrapShoveler]

Okay, so how many times have you been flipping through a file and notice images with 4 color black, (registration, Auto)?

A quick fix to remedy files with more than 300% total ink coverage is to copy the black channel and adjust with levels or curves to make the darkest part of the shadows plug, within tolerance and the highlights taken out. The easiest thing to do is invert the channel so it is a negative image, open levels, auto balance it, then adjust midtones to take away any pixels that will interfere. You will understand in a minute.

Make a new layer, load the channel. change the foreground color to be the correct combination on black you want. I usually go with 40-20-20-100.
Use the paint bucket tool and click in the selection. Now, the first thing to look for is too much black, in which case you need to readjust your "new" black channel and start again. If the file is changing color too much, again readjust your channel. The trick is to make it print correctly without changing the look.
 
You can also use this same technique when modifying 4 color images that need to be spot colors. Like changing the red to magenta and remapping to a spot, or making a spot in PS and saving as a DCS 2.0 multichannel eps.

Try it out.

[frailer]

Nice, DCS. An acrobat.com link on its way to you with file, anyway. Chat later.

[DigitalCrapShoveler]

I await mi Capitan.

[DigitalCrapShoveler]

Finally good to get a response. I had been waiting. :wink:

[DigitalCrapShoveler]

... Since February of last year! :laugh: :laugh: :laugh:

[frailer]

D'Oh!  Meant to reply on the "other" thread.  No matter...    :embarrassed:

[DigitalCrapShoveler]

D'Oh!  Meant to reply on the "other" thread.  No matter...    :embarrassed:

I know you did... and I am laughing! :laugh: :laugh: :laugh: