Out of interest I compared the 12-35 and PL25 1.4 lenses at 25mm FL on Sunday.
For most part the differences weren't too dramatic, the 25 wins overall, just better edge sharpness basically otherwise take your pick.

However one anomaly that I noticed when viewing at 100% was the difference in DOF even though all settings were identical (focal length, aperture, shutter speed, ISO and same focus point).
Here's an example, these are 100% crops of the original shots, both shot at 25mm, f5.0, 1/2500 sec, ISO160.

PL25 is first, 12-35 second. Notice how the 25 has much wider DOF for the same aperture.
Not sure why this is, I took 3 shots of the same scene with each lens and it was the same every time.

Any ideas, just food for thought really.

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G5, GH-3, 7-14, 12-35, 35-100, 25.
RX100

I think the focus is just off (or rather, different). The 25 to me is properly focused, with the in-focus area starting just in front of the birds, while with the 12-35mm it is starting at the saturn wording on the boat (at least, perhaps closer). There may also be a small amount of shake in the 12-35mm image, to my eyes at least, which gives a slight appearance of being out of focus...which is kind of the same as blurred I guess :)

The 25mm image overall just looks sharper and more crisp, whether that is blur or shake in the zoom I can't exactly tell, but either way the 25mm is the better shot.

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G5 | D600 | K20d | K-01 | K100d
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The focus points were the same, as I said I took 3 separate shots of the same scene with each lens and it's the same every time. There's is no shake the shutter speed was 1/2500 enough to eliminate any potential camera shake blur.

Paul

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G5, GH-3, 7-14, 12-35, 35-100, 25.
RX100

If the 12-35 isn't as sharp as the 25, things that are equally in focus will look softer with it than they do with the 25. Depth of field will be the same, but the point of focus won't look as sharp, and things not at the point of focus but still within the depth of field won't look as sharp with the 12-35 as they do with the 25. The point of focus will still be the sharpest point for both lenses.

Are you confusing a difference in sharpness with a difference in depth of field?

No, if you look behind the boat, the ropes and mooring buoys and seaweed are all much softer (i.e. going out of focus) in the 12-35 shot caused by a shallower depth of field (DOF), it's like the 12-35 shot was taken with a larger aperture.
Both lenses are very sharp in the focus zone.

Paul

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G5, GH-3, 7-14, 12-35, 35-100, 25.
RX100

How far away were you from the focus point? The closer you were the more sensitive the depth of field is to having the focus point being slightly different and throwing off your test.

The hyperfocal distance with those settings is 27.2 ft so with an out of focus background we can tell that it had to be something less than that.

Great timing. I just was out on my deck comparing my 12-35mm to my 12mm, PL 25mm and both the Olympus 45mm and PL 45mm. Too many lenses, I know. I shot everything on a tripod with manual focus at the identical point. What I found was that the focus by wire can seem to give you the same point but in reality it may be further out or closer in than you think. I also found that the PL 25mm seems to focus further out than the 12-35 in my tests. I did not see any significant differences in depth of field, but subtle changes of where that range was in the photo. My guess is that my observations are due to focusing technique. I may not have approached focus from the same direction and therefore biased the range one way or another. With this focus by wire, it is a bit tricky.

I did see differences in how smoothly the lenses moved in and out of focus. Interesting.

So, where are the results?

Is this lens truly a "bag of primes"?

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Comments and criticism welcome! It's how we get better!

White G3:P20/1.7:P45-200:PL45/2.8:P8FE:P12-35/2.8

Pictures here: http://troyandmollyalloverthemap.shutterfly.com/

http://500px.com/TroyGorrell

Not ready to publish those yet. However, it is quite good. :)

Looking at the full frame, is the FOV identical? Perhaps the zoom wasn't really at 25mm? Or the magnification at the marked focal length is a bit different?

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