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Advice on 500mm (1 Viewer)


Jan Ebr
Hesitating AF is not typically a lens issue - the lens only moves as it's told - the body needs to decide where and when and if it's focused. The autofocus capability depends on the f/number of the lens for the same body, so with an f/4 lens it will autofocus worse than with some f/2.8 one for example.

A really good test of autofocus is to just check it manually - put your camera on a tripod, point to some fixed object (not moving in the wind for example), autofocus on it and then focus the same object manually on liveview on maximal zoom in preview (I assume your camera has such function), compare results. That really shows you whether the AF is good, I found out for one lens that it isn't and even a relatively expensive "backfocus adjustment" did not solve it.


Well-known member
Thank you for your reply. I realised after I posted I was asking a silly question so deleted the post, but clearly you had responded very quickly. I appreciate it and thank you for your comments on AF. I'm not experienced in lenses of this type so it's a new experience for me and I am getting used to both the camera and lens at the same time and need more time to do that.

I will update on my progress :t:

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