Need Drop Shadow to be Grayscale

[TNTGuys]

I have an Illustrator PDF from a client that has a drop shadow. The drop shadow dialog and color dialog are shown below.

The Illustrator PDF is placed in InDesign and when a PDF is generated from InDesign the color space of the image that is the drop shadow is CMYK, which is the same as when simply opening the Illustrator PDF in Acrobat.

It seems like there should be a way to make that drop shadow a grayscale image but I've not been able to find it. Am I missing something?

Thanks

[Monika Gause · Accepted solution]

You could try if this helps (making the drop shadow differently), Illustrator is a little limited when grayscale is concerned: https://youtu.be/FZCEazruAaI

[Kurt Gold]

Can you share the file from your client?

Can you also tell what PDF export settings you are using in InDesign and show what the Separation Preview shows in Acrobat?

[Scott Falkner]

Is the Illustrator file in RGB or CMYK?

[TNTGuys · Accepted solution]

Thanks, Monika. I'm going to hang on to that one! Would rather not share the file, sorry. The InD output doesn't change any color. The Illustrator file is CMYK.

After further looking prompted by your answers, I see that the Acrobat prefilght color option of "PDF images on Cyan, Magenta ro Yellow plates," apparently, isn't all that acruate!! Looking at the separations perview in Acrobat, there doesn't appear to be anything but black there. Yet it flags the drop shadow as imaging on cyan, magenta or yellow.

Does anyone know if a printer's usual preflight, on a file that should NOT contain color, would flag the image with a color model of CMYK but only containing black? I'm gussing not?

For this situation (just a white box with no stoke that is only there for the drop shadow) simply rasterizing the effect as grayscale will stop Acrobat from flagging it as color. But that does rasterize the object which in other situations would not be good.

Thanks for responding everyone!

[Monika Gause]

If things go wrong with color management, then a CMYK document can get converted from one profile to another when export a PDF from InDesign. And then 100K can end up muddy.