[stoppingdown]

... BIF... In a very very lazy mode:

• out of my window;
  
• without tripod (this morning I was longing for doing immediately something, and my tripod is in my car, and my car has been parked relatively far from home)
  
• after I has not been shooting BIF for a couple of years (and possibly more)
  
• as my very first exercise with my a6000 AF in tracking mode
  
• with focus limiter in the range 10mt -> infinity.
  

The shots below are 25% linear cropping (1500px vs 6000px) of the originals.

 

Very first impressions (subjective, without any attempt to get an objective measurement):

• It's not a speed monster of AF, as expected; even though it is faster at shorter focals, and it's definitely not bad below half of the focal range. With AF programmed for still subjects, in a typical landscape approach, AF confirms in a few tenths of second, absolutely fine; I'd say that it's equal or even faster than my Nikkor 300mm AF-S Æ’/4 (I need to do some more precise measurement). 
  
• Hand helding is a pain, as expected: after ten minutes my left wrist was aching. It's the first time I can experience the feeling of unbalance because of the lightweight of the camera. This also had the effect of violently shaking the lens, and jeopardising the effect of the stabiliser. The larger gull photo below appears decently focused, but ruined by the motion blur.
  
• AF seems to be accurate (the airplanes photos, where tracking was absolutely easy, are properly focused)
  
• In any case, it seems that you can have some satisfaction with BIF, not the ones that fly in a very unpredictable way (I wasn't able to get sharp photos of swifts), but I wasn't expecting that. Honestly the only bird usage I was expecting was with slowly moving ones on the ground, so this is already exceeding expectations.
  

I didn't try the custom modes, which I have already programmed for faster AF. And since I'm seeing some slowness of the camera in moving the tracking cursor in the EVF, part of the performance is due to the camera... I expect better results e.g. with the a6300.

 

I'll post more in the next days.

 

PS Focals used below are: 500mm, 600mm, 400mm, 400mm, 600mm.