Canon EF 300mm f/2.8L USM lens

introduction

the pro level weathersealed 300mm f/2.8 lens is perhaps one of the most popular sports lenses for the professional, particularly when shooting field sports under lights from the boundary
the original version of this AF lens released by Canon in 1987 was integral to Canon dominating the pro sports market when they finally released a pro AF SLR in 1989, and then for the next decade or two thanks to its fast AF compared to the competition in the 1980's, and Nikon did not catch up to the AF speed with such a lens until 1996.
in 1999, an image stabilised version replaced the original version, changing the rear filter size to 52mm, removed the MF speed options, is closer focus to 2.5m and made slightly lighter while tripod mount made removable
in 2011, the lens was again upgraded with improved IS, curved diaphragm blades, close focus further improved to 2m, made 8% lighter again and adds a Power Focus mode for video and new mode 3 IS but tripod mount no longer removable
these are big, heavy and very expensive lenses designed for use on a monopod NOT hand held!

2011 onwards
300mm f/2.8 image stabiliser now 4EV and with new mode 3 IS designed for shooting irregularly moving subjects. The practical implication for this mode is that the image stabilization system is only active during the time the exposure is made
weathersealed
MF is motor driven but no longer has 3 speeds
“Focus Preset” feature which allows rapid refocus to a preset distance
new Power Focus mode for video - constant speed focus pulling, with two speeds available
focus limiters: 2m-6m, 2m-infinity, 6m -infinity
multicoated, SWC coating
16 elements in 12 groups incl. 2 flourite
rear 52mm drop in filter
rear focusing
9 curved blades
close focus 2m giving 1:5.6 (0.18x macro)
tripod collar cannot be removed
128mm diam x 248mm long
2350g (5.3lbs)