I watched the video - and the reviewer started by saying: stick with the same manufacturer for lens/body for best results.
And - focus is likely as important or more so than IS.
The reviewer then said that they switch lenses all the time - but those are up close lenses for humans, not far for birds.
I don't know if it matters - seems like "internet wisdom" (so, take with a healthy dose of salt)
is that the best AF performance is within a single manufacturer for lens/body.
Have also just found this site - I'm eager to look through and see what they've found in the field:
A few years ago, our reader Alfredo suggested an idea for an article. Since we test the autofocus performance of many cameras at the same red kite feeding stations, why not publish a list of all the cameras we use with their keeper rate for birds in flight? I liked ... Read more
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