Can you use this lens without using defocus option as if let's say like that option didn't exist or does the defocus option have to be used regardless?
I'm getting a 1DX soon n always toyed with having an Nikon also n was looking to get nikon 24 f/1.4, 85 f/1.4, and possibly 135 f/2
You can use it normally no problem. The control is used to make the background or foreground(if for some reason you had a unique shot) produce more bokeh.
Leave it at 0 and it functions like a normal 135 f/2.
You might want to consider, since you have a list of NIkon lenses that intrigues you... to buy the D4 that mounts all those lenses without an adaptor, rather than a Canon 1Dx... Just a thought...
The capabilities, unsurprisingly, of the D4 and 1Dx overlap. The 1Dx has 12fps (under some conditions) for typically exteriors and a good buffer with very fast accurate AF except in the lowerst light conditions. The D4 has 10fps, a really huge buffer and slightly slower but accurate AF even in the lowest light. Each Camera has different but effective controls except that there's controversy about the AF points in the 1Dx' VF. Canon's work around seems not to be popular.
I bought the Canon 135 F2.0 and loved it but seldom use it after I got the Canon 200mm F2.0. Essentially, for me, whatever, optically, the 135 did the 200 F2.0 does even more. So when I started with FF Nikon I soon bought their 200mm F2.0. Later I got the 85 F1.4 but never seem to use it. Now the Canon 85mm F1.2 that is an unique and very specialized lens. But then I shoot very little Canon now since the controls are so different it slows me down.
You should look at saving some $$ and getting the 135/2 AIS MF lens. I bought a 135/2 DC and was not impressed enough to keep it. My 135/2 AIS lens was every bit as good as the DC version.
Nikon is rumored to have a 135/1.8AFS coming out - that hopefully will be very sharp wide open and if it is it will be very sweet (and very expensive).
