I got the 12-50mm together with the EM5 but I decided to not unwrap this lens since I'm not very excited about this it and I wanted to return the the howl kit.
However, today when I was "engineering" back the EM5 into its box, I couldn't resist to test the 12-50mm on the GH2. This power zoom work very well and there is a to me never seen before display on the GH2, that indicates the current focal length.
Focus very quick an silent (better than 14-140!)
didn't checked if its parfocal - damn
manual zoom is also ok
looks like this lens is parfocal:
last video on the video review chapter http://www.dpreview.com/reviews/olympusem5/14
Like previous Oly consumer zooms, I suspect this 12-50 works best around ~25-30, and is probably softer at 50. This was true with my 1st Oly zoom 14-54 (S1). What I just said is pure speculation since I do not own the 12-50
The 6.3 is a let down, but I notice that at 12, it is already 3.5. I wonder at what focal will the lens jumps to f5.6 or hopefully something less, like f4 something. With the 14-54, you only need to go to ~17 and it is already at 3.5....
I'll tell you later on, currently got it at home for testing purposes on my G3. So far it does work reasonably well.
Here is kind of review from Dec 4, 2012:
Firmware v1.4 available
Stability of lens aperture when shooting videos has been improved.
http://www.olympusamerica.com/cpg_section/cpg_support_downloads.asp?id=1582&os=w
The Olympus 12-50mm Lens Reborn as an Anamorphic Zoom!
This one of a handful of lenses recommended by SLRMagic for their Anamorphot 1.33X/40 adapter. It fits with no step-up ring needed, and makes for a power zoom anamorphic lens (combo) from 40-100mm (35-mm equivalent). This is the only anamorphic zoom lenses I know of, and saves having to acquire multiple expensive anamorphic lenses.
Works perfectly with the Gh5, which adds IBIS. This was shot in 4K 60p using V Log L.
@kurth In general, because of the size of the adapter lens, only taking lenses 40mm (in 35mm-equivalent) or greater will not vignette. So, the Sony 28mm f2 works fine in APS-C and the Canon EF 40mm works fine in either full-frame or APS-C (which means on an FF camera you can choose between 40 and 60mm with no loss of resolution in video). And the 20mm Lumix mFT lens works fine and this mFT zoom works fine from 20mm through 50mm (40-100) on the mFT sensor.
Note that the Sirui 50mm anamorphic lens is actually 100mm in mFT and 75mm on APS-C cameras. It will not work at all with full frame. That is hardly the best choice for one focal length.
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