Which episode is the "double facepalm" image macro from?
There's a Demotivational-style image macro that features Picard and Riker facepalming at the same time:
I believe the person in the left of the picture may not be Picard in the original scene: the picture of Picard that you see here was probably photoshopped from another scene. But what is the source of the original screen capture?
You're right that the Picard in this screenshot is shopped in - you can see the original Riker-only facepalm on Google images search.
However, none of those image results indicate where this screen-grab came from.
But - I think that this is from Season 3's "A Matter of Perspective" - where Riker is accused of murdering a scientist.
There's an actual double facepalm in Voyager where Q calls himself as a witness and both of him facepalm in response to some statement by Tuvok. Funny that they didn't use that one for the meme.