Hi, When I play piano for a period of 10mins or more when I stop playing my vision is then blurred for a period...maybe a minute or so then back to normal. I play by ear so my eyes arent focused on anything in particular when Im playing - just sort of watching my hand positions. The only other time this happens is if I play guitar but then the effect is only very slight and isnt really noticeable, whereas its very noticeable with piano. Only other sight issues are very occasional "floaters" (black spots floating in your vision) and they are only there a a few seconds. I dont wear glasses (although I used to for a few years some 15 years ago before my eye sight turned back to normal). Im not on any medication either. I think Ive read that FM can cause blurred vision but its seems strange it only happens with piano - and never other times.... Does anyone else experience anything like this ? Thanks.