The Panasonic Lumix G X Vario PZ 45-175mm, as is its full designation is a lens available for a couple of years now. I had recently had the chance to test this telephoto lens for a couple of weeks and here is a quick report about it.
The lens belongs to the latest generation Panasonic lenses with electronic powered zoom. As is evident from its focal range, it is made to complementsimilar 14-45mm power zooms, for a 2 lens "kit" capable of covering photographic as well as video needs.
Build quality can easily be characterized as very good, and is certainly above the average for m43 lenses. Tolerances are tight and the whole deal gives an impression of solidness. It also helps that the barrel does not extend while zooming; less dust entering the lens elements and overall smoother operation.
In use, the lens is quite pleasant to use; on bodies such as the E-M1 and GH4 it balances really well and is as heavy as it needs, not to feel flimsy. It is also quite comfortable with smaller bodies such as the G7 or E-M5, but will probably feel stupid on a Pen Mini or GM5.
Power zooming operation is a bit odd and I admit I never quite got to grips with it. The lens has a dedicated power zoom lever, but, in reality, it zooms by the electronic motor even in "manual" operation, and this takes some getting used to. It is a great characteristic for video though. Speaking of zooming, the lens covers a rather extended focal range, making it very useful as a walkaround lens, or for travel photography.
The AF is excellent in speed and accuracy. Please let's not forget that this is a rather "slow" lens in terms of aperture, so don't expect lighting fast focusing ability in low light conditions; it holds its own though.
Coming to the IQ, the general impression is that this lens stands firmly between the regular kit zooms and the pro zooms in the system. It exhibits above average sharpness and good contrast. There is very little distortion, but there is some vignetting (esp. at the low focal end) but can be reduced in post easily.
Bokeh was a nice surprise, being quite pleasing for a lens in this category. Close focusing allows for some "quasi-macro" use, where the nice bokeh also contributes to a good results.
I had read in previous reports about heavy CA with this lens. I tried to replicate them and this is the worse I could come up (uncorrected photo below). This level of CA can easily be addressed in LR.
What is much more serious, and, in fact the main drawback with this lens, is that, Panasonic and Olympus continue to shoot themselves in the foot by refusing to cooperate in providing 100% compatibility between their products. This lens is one example of that.
It's one thing not being able to correct distortions and vignetting in-camera (where Panasonic lenses work only with Panasonic bodies and similarly for Olympus). Let's say we always shoot RAW and correct in post production. What's more serious is having features fighting each other, such as, image stabilization in this case.
The lens has stabilization which cannot be turned off on itself. Olympus bodies have an option to "prioritize" in-body stabilization, which, in theory, should disable the lens IS. In reality, it sometimes leads to a situation where lens and body try to cancel each other, resulting in soft/blurred images. Below is an example of that: the image is not out of focus, it's just a little bit softened, a fact that most of the times is not visible in the image preview, but, rather, when you look at the images back home. This situation has nothing to do with shutter speeds and is somewhat unpredictable.
Let me emphasize that this behavior is relevant only with Olympus bodies. In this case, the best way to use it is to disable in-body stabilization completely. This is a shame, although not a showstopper. It goes without saying that the lens behaves perfectly with any Panasonic body, even the latest ones with in-body IS.
In conclusion, this is an overall great choice for anyone in the market for an all-around medium range telephoto zoom. Let's keep in mind that this is a "daylight" lens and better suited for those with video in mind also. There is also the caveat about Olympus bodies and (mainly) IS. But apart from this, the lens delivers affordable quality , at a street price of about 250-300 euro new (and less for a used example).
Here is a small photo gallery shot with the lens and the Olympus E-M1: