>That IS interesting! Considering how Giles was "bragging" <g> about
>his 50/1.2 a couple years back, it may be worth a look. I currently
>use the 50/1.8 which I use for lens stacking a la John Shaw and a
>loupe as well as a normal lens. The 50/1.2 can come in handy for
>available darkness photography.
I think that the number of blades in a lens is at leasty partly a
function of the fact that these lenses are for SLR cameras as opposed
to rangefinder types. I a previous post, someone mentioned that the
Leica M-elmarit 90mm lens had about 15 blades. Since there is no
automatic diaphram in a rangefinder camera, a manufacturer can increase
the number of blades without interferring with the operation of the
camera. The more blades there are in a lens, the more friction in the
mechanism. If there is too much friction in the mechanism, then there
would be a good chance that the diaphram would bind and/or the spring
tension required to return the diaphram to wide open would be too much
for the actuating mechanism in the camera body to handle without
breaking. It would also seriously impact motor drive capability in a
SLR type camera. The motor drive in a rangefinder camera only operates
the shutter and film advance, not the diaphram.
Be seeing you.
Six of one.
Dirk Wright
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