Considering Sigma 19mm f/2.8 and 30mm f/2.8 (Original Versions)

I have the Olympus E-PM1 kit. As I have used micro 4/3rds more than my Nikon D5100 stuff as of late, I've pondered adding lenses (and also updating to the E-PM2). I've considered the Olympus 45mm f/1.8 and the Panasonic 20mm f/1.7, when I just tonight learned of the Sigma alternatives.

Then I learn that new versions of these lenses are now out. At any rate, I've found someone selling the original versions of these lenses, and I'm considering them. They're selling both for $200. (Apparently B&H has that this special also.)

Mainly, I'm wanting something for portraits, which would be the 30mm f/2.8 in this case, I've been using an old manual-focus Nikon 50mm f/1.8 via an adapter. I MIGHT would find some use out of the 19mm as well. My thoughts: besides the obvious differences in f/stop speed (f/1.7 vs f/2.8), how do these measure up vs the Panasonic 20mm f/1.7 (I know the Panny is smaller) and the Olympus 45mm f/1.8?

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LRH
http://www.pbase.com/larrytucaz
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