What 27mm at f/2.8 actually gives you
27mm 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 APS-C bodies it covers, it frames like 41mm would on full-frame.
f/2.8 is the working standard for a fast lens — a stop or two of low-light headroom over a kit zoom, and noticeably more background separation.
Size and filters
At 84g (3.0 oz) it is light enough that it stops being a decision — the kind of lens that stays on the body or in the bag without thought.
Filters are 39mm — worth checking against what you already own, since polarisers and ND filters at this size are reusable across any other lens sharing the thread. A dedicated aperture ring gives direct control without going through a camera dial, which mostly matters for video work.
Autofocus and stabilisation
Autofocus is driven by a Stepping motor.
There is no optical stabilisation in the lens, so handheld steadiness depends on the body having IBIS, or on keeping the shutter speed up.
