How to correctly adjust color saturation in picture when preparing it for magazine print?

Question

I made a magazine and all pictures currently are in RGB color mode. Now I need to prepare them for print and after converting them to CMYK in Photoshop CC, their color saturation (black parts) are above 300% and needs to be fixed.

I used Levels option for some pictures and adjusted the black color and this works fine, but I wonder if this is the right way how to do it? Maybe other way would be better?

Is there a way how to remain the black color in picture more sharp than it is after adjusting it in Levels?

I understand that pictures in print would look not so sharp as on screen, but when I see some of the magazines or books where they look very colorful, I start to think, where is the idea?

Answer 1

The basic answer is You have your process wrong, at least the concept of the process.

I need to prepare them for print and after converting them to CMYK in Photoshop CC

The images should not be prepared for print after converting them to CMYK.

They should be prepared and adjusted, on a color calibrated workflow in RGB, and the very last step is to convert them to CMYK.

The black parts are above 300% and needs to be fixed

No, you simply chose the wrong color profile. You probably used one like Fogra 39 that has a maximum ink TAC (Total Area Coverage) of about 330%. Use one like SWOP 2 that has a 300% TAC.

Your provider should tell you what profile to use and what is the TAC they use, some actually can use a TAC of more 300%.

Their color saturation (black parts)

A tip. A black is not color saturated, a saturated color is a bright red, a pure yellow, etc. A nonsaturated color is gray, white and black. You are refering to saturation of ink, not color.

Another way would be better?

The workflow is:

• Calibrate your monitor
• Use the right CMYK color profile
• Prepare your application to use this CMYK color profile to simulate it on screen so you made the adjustments on how you want the print to look like when converted from RGB to CMYK and printed.
• Convert the image using that color profile and the colors and ink amounts should be right.
• The printer should follow the ISO specification to achieve the correct color.
• It is highly advisable that they provide you a color calibrated hard copy of it to be signed and used as a visual reference.

Is there a way how to remain the black color in the picture more sharp...

Again, you are mixing concepts. Sharpness has nothing to do with black, or any color for that matter, sharpness is how the edges of an image are seen compared with the surrounding area.

I start to think, where is the idea?

A color calibrated workflow.

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An important note: Preparing files for a magazine is not a trivial task. You are potentially facing a big economic loss. Have a professional to double check this files prior to print, including the printer and have the color calibrated hard copy signed and authorized by the final client.

This hard copy is not exactly the same color than the final product because is using a different system and the print itself has some variations, but it should be into a reasonable range.

Answer 2

Of course only printable colors can exist in a magazine, but the appearance of the colourfullness of the images depends also on what else is visible at the same time. That's why the color decisions should be done at the layout work (InDesign or equivalent)

Think about the following: The print process can produce some well saturated colors. You have used them generously for the title and vector elements. Your photos can look out a little uninspiring in that company.

The things do not get better, if the text on the same page calls for rich colors (the glorious floral splendor or something)

Worse: Your layout has been accepted after seeing the glorious PDF onscreen. If you now in a deep silence flatten the colors to be printable, do not expect to keep this job.

You should take the whole layout under the work. Have the final output color settings (from the printhouse) in use. Oversatureted photos get muddy due the clipping. Adjust the colors to printable range. Also adjust the photos to show their best in the printable range. For example, If some part of a photo needs a good saturation out of gamut (=unprintable), you in some cases can do a selective hue shift.

(Note, you can't radically change brand colors and well known color relations, some changes must be unnoticeable)

Generally you need the levels (or preferably curves) adjustments to have good contrast in midtones. That's highly dependent on the image content and must be done in accordance with the color balance settings.

If somebody expects somehow more saturated final result due the glorious proofreading PDF, you shold NOT keep him unaware about the printability and what are the consequences, if one does nor honor the gamut limits.

Answer 3

You can apply Grey Component Replacement and Under Colour Removal to lighten the ink load on the substrate. This is done in the colour break preparation by pre-press workflow.

GCR - Grey Component Replacement substitutes a black halftone for equivalent amounts of the colour inks throughout the full tonal range of the image.

In printing, under color removal (UCR) is a process of eliminating overlapping yellow, magenta, and cyan that would have added to a dark neutral (black) and replacing them with black ink only, called a Full Black, during the color separation process.

Try this:

In Photoshop, select Edit > Color Settings > CMYK > Custom CMYK.

Under Custom CMYK > Ink Colors, select "SWOP (Newsprint)", and click the radio box "UCR".

Also you might set Total Ink Limit to something less than 300, like 280.

Now when you convert your RGB to CMYK, there should be a lot less CMY under your K.