the lens mount on my T90 has become slightly loose, so that lenses, when attached, can 'jiggle' slightly. it's really only a tiny amount of 'play' in the lense position - maybe 0.5mm - but as the direction of movement is directly away from the film plane (ie the back of the lens comes away from the camera ever so slightly) i'm not sure if it may affect sharpness. i realise that if i did a lot of macro work (which i don't) this could be a problem, but in normal use is it something to worry about? it's annoying, but i don't want to pay for a repair which isn't necessary. i usually use lenses between 28-200mm, often wide open. alternatively, if anyone knows how it could easily be tightened that would be a great help. i had a look round the mount but couldn't see any obvious tightening screws.