Shadows have a grey shade when saving as a PDF from Illustrator.

[Nowhereboy11]

I created transparent shadows in Photoshop.
Saved (CMYK) as a .psd document.
Opened it up in Illustrator and applied it under the main image.
In Illustrator, it looks good (a slight darker shade of the background color).
When opened up in illustrator, everything looks fine.
Here's the problem. I had to also save it as a PDF.
But when I open that PDF file, I get this grey shade either at the ends of the shadow or middle.
Can this be avoided? This is a print file for packaging and I have to show the PDF to someone and this will look really misleading.

[Monika Gause]

Which PDF viewer? If Acrobat, is it set to simulate overprint?

[Nowhereboy11]

It's Acrobat and yes, it's set to simulate overprint. 
I opened a similar file in Acrobat saved from Illustrator from an old collegue and that PDF file opened up in Acrobat looking as it should. 

[Anubhav M]

Hello @pbampos,

We understand that encountering technical issues can be frustrating. Would you mind sharing some more details, like the exact version of the OS/Illustrator, public links to sample Ai and PDF files after uploading them to Dropbox/Google Drive/etc., and the exact details of your entire workflow and settings used, including a screen recording (https://adobe.ly/45cQZKh), so we can investigate this further?

Looking forward to hearing from you.

Thanks,

Anubhav

[Ton Frederiks · Accepted solution]

Attributes like blend modes do not transfer when images are placed in Illustrator.

The drop shadow may be set to multiply in Photoshop, but that only works for layers in Photoshop.

Apply the dropshadow in Illustrator if you want it to interact with Illustrator objects.