On Wed, 28 Oct 1998 06:17:43 GMT, zhupanov@usa.net (Sergey Zhupanov) wrote:

>I have seen references to using teleconverters on:
>a) macro lenses
>b) wide and super-wide lenses
>c) fisheye lenses
>
>Could someone please explain the effect such combination
>achieves. I thought that 1.4X teleconverter simply made the
>effective focal length to be 1.4X the original. But I suspect
>there is more to the story here...

Those references were mine...;-)
a) -- greater magnification without loss of infinity focus,
and/or greater front space with the same magnification
b) -- the Nikkor 28mm f2.8 *AIS* both focuses very close
and is excellent at close focus - the converter can use
that to provide a decent macro lens if you own that 28
and the TC14A but not a macro lens; the TC14A can be
useful with WA PC lenses to provide greater FL and
greater available shift
c) -- the TC14A on the 16mm fisheyes makes a nice
"people-kind" super-wide; the TC14A on an 8mm fisheye
gives a larger image, but still gives 180 degrees of
coverage (I've used this to shoot a whole large building
facade, while standing inside a tree line about 20' from
the building - the "distortion" was acceptable, since
there was no other way to shoot the unblocked facade
in one photo any other way...)
As with some teles and a few zooms, some short lenses
perform well on TC's - and the combinations can provide
"lenses" that otherwise don't exist.