On 24 Jan 2011, at 4:56 PM, Sawyer, Edward wrote:
> "at f/3.5 across the frame (it resolves > 100lp/mm *on film* in the
> very furthest corners
> at that aperture)."
>
> Um..., seriously unlikely, if not downright impossible. Physics of
> film/image making apparatus make that basically impossible even in
> theory. I am sure it's a nice lens though. ;-)
Ed,
I am sure that I do not possess the equipment or skills to coax this
out of my lens/camera
combination, but this is certainly not theoretically impossible! No
less possible than Zeiss
coaxing 400lp/mm out of their Biogon 25mm f/2.8 lens, *on film*. It
doesn't mean that it's
a "useful" image (nobody said anything about contrast), but the
resolution is there, and
proven (Zeiss will surely not lie in their official publications):
http://www.zeiss.com/__c12567a8003b58b9.nsf/Contents-Frame/30536193ed0c97a7c125711c006fc2c2?opendocument&click=
I have not myself *seen* 100 lp/mm in the corners of my images, but
authoritive testers have claimed this,
and I have no doubt that if a 25mm wide angle can resolve 400lp/mm in
the centre, that (basically the
word's best) 50mm can resolve 100 lp/mm in the corners.
Anyway, I don't really care that much - I like taking photos and
making nice big prints! I have used
many 50mm lenses, and nothing has come close to the Heliar for my
purposes. It's the first time I've
made big prints, where the detail really is right down to grain level
(and I'm talking ISO 100 film
here), i.e. almost adjacent grains have very different intensities.
Never got that out of my Zuikos,
but I am not giving up trying!
:-)
--
_________________________________________________________________
Options: http://lists.thomasclausen.net/mailman/listinfo/olympus
Archives: http://lists.thomasclausen.net/mailman/private/olympus/
Themed Olympus Photo Exhibition: http://www.tope.nl/
|