This is from PMs that user Storch allowed me to publish:
I still have one question about Sigma 400mm f/5.6 APO macro. What do you think about AF speed of this lens? Is it suitable for action shooting (e. g. for birding)?
I'm not a birder, so I can't tell.
But on my D300 it takes around 1 second to go from infinity to 2.5m plus a lag before the focus motor starts to work depending on the brightness of the scene. Indoors this phase can add another second to focusing, but in brightly lit outdoor scenes it is almost imperceptible.
Thanks for answer, Thomas. I am not a birder too, just think it would be interesting for me. But I cant make big investments for long lens for the moment, so I try to find something old, relatively cheap but decent.
Yeah, the Sigma 400/5.6 APO macro is decent lens and quite cheap too if you can get hold of a used copy in good condition.
Btw. In my Sigma 120-400 OS lens-review there are some comparisons to the 400/5.6 lens. Just have a look here
Thomas (beware: Nikon-fanboy and moderator!) My Lens Reviews
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