Just out of curiosity, how are you optically experiencing the Sigma 150~600 Sport vs the Nikkor 80~400G, Will?
Keeping both, should say something. AF speed is the same (props to Sigma going to 600mm)
I'll be using the D800 80-400G combo for my lightweight BIF rig. The D810 will get the Sig Sport
on a 2nd BushHawk. As for preliminary IQ results...the Sig wide open at 500mm is on par with the
80-400 wide open at 400 and that's impressive. Will have to spend more time at the 600mm FL as
I've never shot that 'long' before. Right this minute I'm liking the results around f8 @600 and keeping
the SS up (1/2000th) I'll get better re: acquisition and hopefully dropping back to ~1/1600th for BIF and
stuff that moves. Been shooting BIF for over 20 yrs the learning curve won't be very steep. HTH, Will
FWIW, I've yet to see a need to fine tune the Sport. The 80-400 is at -7 and -4 respectively. @ 0 on my D3/D600
Even my D2Xs plays well with the Sport. Amazing!