Olympus Zuiko 17mm vs Panasonic Lumix 20mm

Dunno. As Pekka points out, haloing is a lot less on the Olympus as is CA. I haven't experienced much of it with the 20mm, but I also have only borrowed a copy for a few hours and didn't shoot much that resulted in it. The Panasonic 14mm is supposedly as bad give or take a little and I can speak from experience, with some backlit shots, especially with small objects that are backlit (girders, wires, ets) it can be a pain in the rear to remove CA and reduce haloing. I love my 14mm a lot, but I HATE using it shooting against strong light with small objects. Sometimes I am lucky and a quick CA removal check box click takes care of it.

Other times it can take me 3 or 4 minutes to clean up an image and I am not always 100% successful without manually desaturating areas which can add 10 or 15 minutes to an image depending on how bad it is.

The Olympus 17mm looks significantly better in this respect.

Combine that with fast focus and silent focusing and that is a pretty big win. For me personally you also have a slightly wider angle of view (I like 17mm/35mm equivelent, I don't like 20mm/40mm equivelent). The last thing I can think of is that extreme corner sharpness appears to be higher. I don't often need maximum extreme corner sharpness, but I do like my image plane to be nice and even resolution across. The 17mm seems to deliver that, even if center sharpness isn't quite as good.

Bokeh also looks pretty nice in the shots I've seen. I don't like the 20mm Bokeh.

So what do you have with the 20mm, slightly better center resolution. around 1/6th of a stop faster and slightly smaller size.

That isn't much of an "advantage" when compared to significantly faster focusing (if the 17mm focuses as fast as the 12, 45 or 25/1.4, then less than more than twice as fast as the 20mm) and quiet. Better extreme corner resolution and better micro contrast. Bokeh is a bit of personal taste, but a number of the early reviews are certainly showing nicer Bokeh then I see out of the 20mm and several of the reviewers have also stated that. Better build quality too and if you care about manual focusing, the pull back ring can be pretty useful as well.

Frankly I am glad that it came in at the price it did. If it had been $399 I would have been forced to buy the 17/1.8 post haste and sell my 17/2.8. As it is at $499 it is cheap enough I am strongly motivated to buy it, but not so cheap I won't be buying the 12/2 first (probably this spring). It also isn't so expensive that I have to mutter curses at Olympus whilest I buy a copy at some future date (though more than $599 and I don't think I'd ever pony up the money for it. It seems to be worth roughly $500. To me at least).

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