When Grayscale does not mean Grayscale in Photoshop - care needed on saving

Unchecking it is not a solution.

Using the right grayscale profile for the purpose is the solution.

If this is for offset print, and you want to print on the black plate only, the way to do that is to use the black ink component in the CMYK profile. So first you need to know what CMYK profile is used for the actual process.

Set it up in Color Settings as follows. Click "load gray" in the rolldown for working gray, and navigate to the appropriate CMYK profile. It will look like this:

Once you've done this, you can convert to it as a grayscale document profile, and this is what you should be working with. Then it will appear correct out of the press.

The Dot Gain profiles are generic and basically outdated and useless. Dot gain refers to ink spread in the paper, but it's not a fixed percentage; rather an irregular curve. It's built into the CMYK profile.

For other purposes, grayscale is very risky and should be avoided if possible. The reason is that almost no application on the planet outside Photoshop supports grayscale color management. No, there is obviously no color involved, but the tone response curve is determined by the grayscale icc profile. So a standard color managed process is required for correct handling of the tone curve.

Since that is very unlikely outside Photoshop, grayscale is very unpredictable. To get it to roughly right, you need to use a grayscale profile that matches the intended output.

If you are creating page-layouts with text in Photoshop you may want to re-evaluate your workflow. 

Could you provide one of the pdfs you deem »correct«? 

What were the pdf settings? 

Let me move this to the Photoshop forum for you, which is the appropriate forum for your question.

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