I have used both. I own the 500 II and I have borrowed the 400 DO II from Canon.
I shoot the 500 handheld the vast majority of the time. It can become cumbersome after carrying it all day and the 400 DO II will be easier to handhold and easier to swing for birds in flight.
IQ wide the 500 is better IMO with better micro contrast. This will be compounded if you are using teleconverters, ie the 500 + 1.4 compared to the 400 DO II + 2x.
The 400 DO II is one of the fastest focusing lenses I’ve ever used.
Lastly, I will say that the 500 II with a 100-400 II makes a created combo whereas if you go with the 400 DO I would say the only combo that makes sense is to pair it with a 600mm.
Jun 18, 2019 at 03:16 PM
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