(All) The one difference you will all notice is that between the ages of 50 and 55 (or thereabouts) you will lose the ability to change the focus of your eyes. Regarding your eye as a camera, you could say that the lens is still quite clear and forms sharp images, the film is more-or-less as good as it was, but the focussing mechanism will seize up and there is nothing whatsoever you can do about it except get reading glasses.
(flerdle) My knuckles graze the floor. This of course is why I play the trombone. Where are you, for it to be 43°C? Not Oz, at this time of the year, surely? A pleasant 18°C here. Sun in and out. Light breeze. Very British.
I thought one was only a Fresher for about the first two weeks of first year... But I must say, I think Freshers' Week is wasted on the Freshers - much better in subsequent years.
You're old if you're old compared to your friends, and young if not, I think. (My friends range from 11 to 60+, and I'm nearly 29, so I get to feel young and old - and I spend my time either enviously wishing I was older in terms of experience and knowledge or younger in body).