[skysurfer]

I notice that finding stars in twilight is getting more difficult (I think) with the naked eye. With telescope (even in full daylight) and / or at night I notice no difference with 20+ years ago.
I suspect that the autofocus mechanism in the eyes is slower for older people like me and peering into the blue void is behaving like a camera with AF on pointed on the blue void.
I remember that I found Sirius with the naked eye in full daylight along the scope when looking along the telescope which showed Sirius on a late March afternoon from Canberra in 1986 as a very faint point. Here in Holland I (barely) saw Arcturus in May 1982 at sunset with the NE.
Now I cannot see Arcturus at sunset even when looking along a scope.

Is this due to the slower AF of older eyes ?