On 22 Mar 2003 at 10:56, Keith Green wrote:
> > > >I wasn't thinking of building one into the body, but a removable
> > > >one that could be inserted between the body and lens, like TCs.
>
> Why between lens and body?
>
> See http://www.speedgraphic.co.uk/pdfiles/p11-13.pdf
>
> for the Ohnar super wide-angle / fisheye converter.
But that's on *top* of the lens too, not between lens and body.
> For non-interchangeable lens digital cameras and cam-corders, the
> majority of manufacturers seem to produce their own converters, in
> both wide-angle and tele versions, which have to push on the front of
> the lens.
This one too....
The only concept close to such an inbetween piece of optics was one
of the older Fuji/Nikon digi-SLR's....it had a ordinary non-full-size
chip, but with enlarging optics mounted on top of it, deep inside the
body, acting as a full-size chip.
Might as well have been a socalled 'fused optics', a few thousand
optic fibers glued/melted together, one end pressed tighter than the
other, thereby creating an enlargement effect....
Never seen it again (the fused optics concept is not rare or hard to
find, it can be bought from Edmund Optics, including applications as
a desktop enlarging-glass/press-papier), and I believe it suffered
from quite some light losses....and it might also only be feasible
with low-resolution applications, as you can press only so many
fibers in that chip-area....
Other than that, one must almost assume that the optical concept
(with non-fused optics) is downright impossible, otherwise some
aftermarket company *must* have jumped at this opportunity....
I *think* I once even asked this question in the Usenet newsgroup
sci.optics, many moons ago, but never got any answers....
Never seen any elaborate/expert discussion about this either, so it
probably is a bit more braincracking (even to falsify the
possibility) than we think....:))
--
Bye,
Willem-Jan Markerink
The desire to understand
is sometimes far less intelligent than
the inability to understand
<[EMAIL PROTECTED]>
[note: 'a-one' & 'en-el'!]
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