Photo stream shutdown
Is Photo stream shutdown only effecting images on my Apple TV or does it apply to images in Phots on my iMac as well
iMac 27″, 10.14
It applies to any Apple device where you were using Photo Stream.
See instructions in Information about the My Photo Stream shutdown - Apple Support
If you don't have the My Photo Stream album in the location described in that support article, you won't lose any photos.