Export to PDF Issue - .pdf showing edges of a placed .png

[Marley C.]

I'm working in Illustrator 26.4.1. (64 bit)

The light blue image shown here was made in photoshop. I cut out the sillhouette from a high res photo, and did a solid color fill adjustment layer. I exported it to .png with a transparent background, and placed it into Illustrator. At this point, all looks great! Until.... I export to .pdf (as a High Quality Print).

When I export to .pdf, you can see a dark border around the edges of the shape. This does not disappear when zooming in. 

Any suggestions?

[Monika Gause]

Does the same happen when you save it as a PSD and place that into Illustrator?

[Marley C.]

Hi! Thanks for the reply. Yes, in fact, the lines are even worse when I place it as a psd.

[Monika Gause]

Are you sure that those dark "shadows" are not in the raster image?

[Anubhav M]

Hello Marley C.,

Sorry to hear about this experience. As suggested by Monika, it could be possible that the shadows are a part of the raster image. Could you try replacing the silhouette with a different image and export it as a PDF to check if the issue reappears? Also, try placing the silhouette on a new document, export it as a PDF and share your observations. 

Looking forward to your response.

Thanks,

Anubhav

[Marley C.]

Thank you for your reply! 

"Try replacing the silhouette with a different image" 

[I replaced it with a different image, but similar in that it's a .png file, solid fill silhouette with a transparent background. This did not produce the same result, although in my opinion, the edges are not very smooth especially when I zoom in.]

"Try placing the silhouette on a new document and export to .pdf"

[Did this also, and it did not product the shadowy edges!]

If I zoom in, I can see some shodowy edges, but not nearly as bad as last time. What does this mean?

[Met1]

"I cut out the silhouette from a high res photo" - how?

Also, I assume you are planning on doing something else in Illustrator?

[Marley C.]

Thanks for the reply. I selected the part of the image I wanted to make into a silhouette and removed the background. Refined it using select and mask. Then I did a solid fill color. 

"I assume you are planning on doing something else in Illustrator?"

[Not sure what you mean by this question. The answer is yes, I workin Illustrator almost every day.]

[Ton Frederiks · Accepted solution]

The sillhouette examples you showed are very good as vector artwork.

You may want to try Image Trace to convert a high res image to vector.

The result may need some refining but will be scalable without showing pixels.

https://helpx.adobe.com/illustrator/using/image-trace.html