What 45-200mm at f/4 actually gives you
45-200mm sits close to the way the eye takes in a scene, which is why this range tends to get used as a general-purpose focal length. On the Micro Four Thirds bodies it covers, it frames like 90mm would on full-frame.
f/4 is a moderate maximum aperture. There is less low-light headroom and less background blur than an f/2.8 lens gives, which is generally the trade for lower weight and cost.
Size and filters
At 370g (13.1 oz) it sits in the middle for handling: substantial enough to feel planted, light enough not to dominate the kit.
Filters are 52mm — worth checking against what you already own, since polarisers and ND filters at this size are reusable across any other lens sharing the thread.
Autofocus and stabilisation
Autofocus is driven by a Stepping motor.
Optical stabilisation is built in, which stacks with in-body stabilisation on bodies that have it and does the work alone on bodies that do not.
