2 okt 2005 kl. 11.39 skrev Bob Talbot:
I feel it´s a pity that DSLR designers stick to Oscar Barnack´s
1914 decision to use 2:3 instead of taking the opportunity to
use a more harmonic 4:5. But that´s an
aside thought...
Per
I agree.
I find 2:3 a bit too "long" and generally end up cropping for width.
The problem I didn't think of till recently is that most of my lenses
(well, the shades anyway) would no longer work. Since many of us have
more cash "invested" in lenses than camera bodies it would have been a
brave DSLR maker to go that route.
I can't be 100% about whether all SLR lenses could be adapted to use a
"full frame" 4:5 image circle (that is, not a 2:3 one cropped down)
but certainly the very wide ones I have seem to have internal
"baffles" which might stop that.
...
Keeping strictly OT... ;-)
The optics within the lenses should have full rotational symmetry,
and thus give a circular field of usable image. Within that circle,
a 30.6 mm square (say) would fit just as well as a 24x36 mm
rectangle, and be covered with the same quality.
Some of these "petal" lens shades wouldn´t work, that´s true, but I
´ve not seen any lens with that kind of rear baffling (possibly I´m
not enough of a W/A man). As for truly internal baffles (between
lenses), I´d have guessed they would have to be circular, since they
are too far from any image plane for other shapes to make sense.
Per
Per Öfverbeck
http://foto.ofverbeck.se
"In a world without walls or fences, who needs Windows or Gates"
