Hi All, I've had the 24-105L for four years and it's my most used lens. Recently it developed the dreaded aperture circuit problem which seems to bedevil this lens once it matures - froze on apertures above F4 and had to get ribbon cable inside replaced...not cheap either.
Hadn't used it much since, but playing around today I started to notice it no longer appears as sharp in the centre wide open... sure there was always a deterioration in sharpness in the corners, but now I'm seeing a drammatic increase in sharpness moving from f4 to f5.6 and again to f8 in the centre. I've always felt in the past the lens was very sharp in the centre even at F4 at least not appreciably softer than at F5.6.
Wondering now if some lens elements may have got misaligned when the aperture problem was fixed... or maybe I'm just noticing something that was always there...since getting the 70-200 2.8 mk2 I confess to have a new standard for sharpness so maybe it's just me.
What's the prevailing view on the 24-105 ...do others notice a big difference in sharpness from F4 to F5.6 esp at the long end?