« on: March 09, 2013, 10:24:28 PM »
The two versions of the 200mm f/2.8L are identical optically. Cosmetically, version 1 has an in-built retractable hood, whereas version 2 lacks a hood (which means you will have to purchase one separately if you require it). It is a great lens, small and inconspicuous (not white) but does feel somewhat long for environmental portraits.
An 85mm lens will frame similarly on full-frame as your nifty-fifty did on the T1i. You would likely feel right at home using either the following on the 5dII:
canon 85/1.8 ($325)
canon 100/2.0 ($350)
I personally prefer the 100/2, but to each their own. That would leave you with enough cash to put towards a telephoto zoom for close wildlife like the:
Tamron 70-300 VC ($275-325)
Canon 70-300 IS ($300-350)
Canon 70-200/4L non-is ($450-500)
I have owned all 3, and quickly sold the Canon 70-300 non-L IS after purchasing the Tamron. Benefits of the f/4L lens over the Tamron: build quality, aperture, autofocus accuracy & speed. Advantages of the Tamron: focal length, 3-4 stop stabilization, color, cost, included accessories, warranty. 100% pixel peeping at 200mm showed me no discernible difference between these optically using 10xLV. Although 300mm on the Tamron is not superb, it clears up nicely with a bit of contrast/sharpening in post.
If you are looking for the best single lens for your cash outlay, then the following come to mind:
Sigma 85/1.4 ($750-800)
Canon 135/2.0L ($750-800)
Canon 70-200mm f/4L IS ($850-900)
Canon 200/2.8L + 1.4x extender ($650 + $150)
The included prices are rough used-price estimates. Nice portraits by the way!