05-31-2013, 07:08 AM
The oly is almost 3x zoom, whereas soLong's proposed lens would be under 2x. That should help on the design. I'd say Sigma's 18-35 f/1.8 is a better comparison point, even if it is only for crop sensors. Since that has to deal with wide angles the retrofocus design would be more complicated than a 45-85 would be. The bigger image circle if you want to use a 45-85 on FF would not help. So, f/1.2 is unlikely to happen at any sane cost/quality. If you slow towards f/2, I think that is a possibility. Of course if we slow down much more, we're into the ball park of a 24-70 f/2.8 again.
<a class="bbc_url" href="http://snowporing.deviantart.com/">dA</a> Canon 7D2, 7D, 5D2, 600D, 450D, 300D IR modified, 1D, EF-S 10-18, 15-85, EF 35/2, 85/1.8, 135/2, 70-300L, 100-400L, MP-E65, Zeiss 2/50, Sigma 150 macro, 120-300/2.8, Samyang 8mm fisheye, Olympus E-P1, Panasonic 20/1.7, Sony HX9V, Fuji X100.