I'll also hide a few things in the photos.
How many photos will depend on how I feel.
But I'll always tell you how many to look for,
so you're not searching incessantly for hours on end.
For example, if there's one photo with a hidden detail,
I'll ask you "Did you see it?"
If there's three, I'll ask if you saw all three.
Once you find the one (or three), you can stop looking.