How dose the cold cause the lens to focus differently?
Dan
Pop Photo had an article a month or two back about zooms and super-teles
that focus _slightly_ past infinity at desert temperatures
so they will +barely+ reach infinity at arctic temperatures.
If the infinity mark lines up next to a "L" shaped index mark, instead
of a purely vertical "|" one, it's a common way to display
the idea it's been designed that way.
While a 180 / 2.5 is neither a zoom, nor a super-tele, I just thought
I'd mention it. Maybe it's so darned fast it has the same
kind of variablity with temperature?
Lama
> Tamron 180 2.5
> It will go just a bit past infinity in focus, after reaching it, I can
> still go a little more noticing the focus screen split image shift.
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