What 50-400mm at f/4.5 actually gives you
50-400mm 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.
f/4.5 is a slow maximum aperture, so this leans on good light or on a stabilised body.
Size, close focus and filters
At 1130g (2.49 lb) it has real presence on the front of a camera, though it stays hand-holdable for a session. A tripod collar is included, which moves the mounting point to the lens's centre of mass rather than hanging the weight off the camera's tripod thread.
Maximum magnification is 0.28x, enough for close-up work on flowers or detail shots without reaching genuine macro reproduction. It focuses as close as 72cm.
Filters are 82mm — 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, stabilisation and weather sealing
Autofocus is driven by a VXD 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.
The barrel is weather-sealed, so rain and dust are a manageable risk rather than a reason to pack up.
