Blacks turn dark grey after exporting to pdf from InDeign cs6

There isn't just one perfect setup.

There may be one perfect setup for the specific job you're creating, but the "perfect" rich black is different for newspaper printing than it is for magazines, as it would still be different for sheetfed printing on coated stock as it would for running it out on your office laser printer, which would be different still for producing a job that'd only be viewed online. That's why InDesign lets you set the perfect values for any job you may be producing.

The "perfect" black would be right for one of those possibilities and anywhere from not quite as good to entirely wrong for the rest. That's why InDesign lets you set up your rich black color settings to accommodate each of those possibilities as necessary. That's also why it's important whenever you're sending a job out of house to be printed to have the corrrect color settings to produce that specific job.

Your print rep is your friend here, and the good ones are perfectly happy to share the correct settings to get the best results. They want you to be happy with their work and keep coming back.

Hope this helps,

Randy

Wow. I hope you're not using that for commercial four-color printing.

400% total ink coverage, I'm sure, looks very black onscreen. But that's going to soak any paper substrate you run and gum up the press something fierce.

I don't know if this is the correct answer. It looks like a very bad cure to me.

Randy

How do you “output a PDF?” Assuming that you use InDesign's Export PDF function, there is absolutely nothing in Windows that is involved in the production of that PDF file or display of same via either Acrobat or Reader. If you are “printing to PDF,” you are in a totally non-recommended workflow that could be affected by Windows updates, depending upon how you are printing to PDF.

Provide more information, please, including how you create PDF and how you view it plus OS version.

          - Dov

I had no conversion...these were my settings.

Right, your CMYK values are being exported unchanged, but the preview (or the conversion of the CMYK values back to your monitor's RGB space for display) in the different programs might change depending on the CMYK profile or color settings being used when you view.

If a CMYK profile is included with the PDF, Acrobat Reader and Preview will use the profile for display, but it looks like Preview doesn't use black point compensation while Reader does:

InDesign, Preview, Reader (ID has black point compensation turned on):

I think that may have been a conscious choice (to leave a Rich Black out). Almost every output device has a different ink coverage threshold, and coupled with different color profiles this usually means there are different specific rich blacks. I work for a printing company and we have 3 different rich blacks that we need to use for our 7 devices.

In most cases, mixes like the ones Peter mentions above will work fine across multiple devices. But it's hard to define a true standard when machines and color management are constantly changing.

Registration is a rich black, but not one you should be using for any printed project. It's a special color that is made of 100% of every ink in the document and is designed for putting marks on the various color plates when the separations are made. Using it for anything else will result in ink puddling and offset onto the back of the next sheet on a press or toner flaking off your laser prints on many papers.

A more typical rich black mix would be 80, 70, 70, 100 or perhaps 70, 60, 60, 100 for a sheetfed press and 50, 40, 40, 100 for web, inkjet, or laser, but but you should check with the printer to see what they recommend. Rob may pop back with other recommendatins based on specific profiles, but keep in mind that although a profile may allow a total ink of up to 350% coverage, in practice it's usually better to stay below that for large areas as it's easier to control when actually putting the ink on paper.

Rob, I do know that. My comment was just a further recommendation for avoiding similar issues sometime in the future should the OP actuall want to do a grayscale conversion. It isn't obvious that the Output All Blacks as Rich Black setting has no effect on cmyk or RGB exports, but does on grayscale. It took me more than a few years to (and maybe some input from you) to figure that out and get solid type on one-color prints.