@dimonió - linked from Flikr photostream - right clicked photo and copy location into
http://farm5.static.flickr.com/4033/...d6844dff_m.jpg
does not seem to work from individual photo, although I´ve managed to do it before!
PS after looking in Flikr forum!
open photo, click on "all sizes" above it (this now medium size)
copy link URL & post as before
Good luck!