Lens Vivitar 2.5/28 Canon C/FD

Lens Vivitar 2.5/28 Canon C/FD
Product description

Vivitar 28mm f/2.5 - approx 1975
Vivitar 28mm f/2 (Kino -22) - approx 1978 (also Tokina, Komine and Cosina
versions which are different again)
Kiron 28mm f/2 - 1980

The main difference is in design, the lenses are a generation
apart. The Vivitar 28mm f/2.5 has a massive front element with a filter
ring that takes a whopping 67mm filter

Improved design means the front element of the later lenses sits closer to
the mount allowing the smaller front element. But apart from this, not much
has changed between the Vivitar f/2.5 and f/2 lenses, both use a
three-quarter turn from near to infinity, with the first quarter of a turn
taken up from 0.3 to 0.4 metre. One other difference I've just spotted is
that the f/2.5 front end does not rotate with focusing, whilst the f/2 does.