Originally posted by Marc Sabatella What do you mean it "turns into" 4.5? If you are at 70mm and in Av mode, and turn the dial as far as it goes, are you saying it stops at f/4.5?
If so, are you *sure* it's the new version?
Yes, in Av mode ;( I turned it as far as possible.
Yes it is the new version... because the old version doesn't have HSM and OS.
It clearly says 2.8.-4 though...
Originally posted by Laurentiu Cristofor Could be some issue with the camera sensing badly the aperture. On one of my lenses I've noticed that the camera was displaying different aperture values when the lens was wide open. Even more strange is the fact that yesterday I was playing with a Tamron adaptall lens connected via a plain K mount adapter and I noticed the camera was recording some random aperture values even though the display was showing f--.
Does the camera overexpose slightly when it displays f/4.5? If you notice this, then your lens is f/4 but the body reads that badly - it should affect exposure, but doesn't make your lens slower.
Another idea is to try and clean the mount and lens contacts - might help.
Eh... the exposure seems fine to me... but is there a way to check?
I'll try to clean the lens contacts.
On second thought... I don't know what I'm doing... so I researched on how to clean the lens contacts... rubbing alcohol on a cloth? is that correct?
I actually do see a black line across, looks like it was from putting it on a camera (or a similar motion..?)