> At first glance this seems likely, but is it true? Does the
> close-up lens
> increase the effective focal length of the lens (and does that
> matter in
> itself?), and do you maybe get light loss by making the image
> circle bigger
> so you get less light on the film, for instance?
I don't think a supplemental lens (close up
filter/lenses/inverted primes), INCREASE the effective focal
length, but actually decreases it slightly. Could be wrong
here. The newer macro lenses by C*n and N*n with I.F. actually
shorten the focal length as they close focus, so your 200mm lens
at infinity is more like 160-180mm at 1/2 life size.
It really is true that there isn't any light loss, except for
the minimal loss of the typically uncoated screw-on lens
elements.
> I haven't sorted this one out. If nobody 'phones me to go to
> the pub this
> weekend, I will be thinking about this one (maybe).
Dave, you're thinking too much. Go play.
AG-Schnozz
__________________________________________________
Do You Yahoo!?
Send instant messages & get email alerts with Yahoo! Messenger.
http://im.yahoo.com/
< This message was delivered via the Olympus Mailing List >
< For questions, mailto:owner-olympus@xxxxxxxxxxxxxxx >
< Web Page: http://Zuiko.sls.bc.ca/swright/olympuslist.html >
|