On Mon, 1 Jun 1998 18:48:32 -0700, BILWIL@webtv.net (BILWIL) wrote:

> Have been shooting for quite a few years, and have done my share of
>macro
>shots. (Have owned several Micro-Nikkors) So I don't consider my-
>self a total incompetent.
>
> The thing is, now I want to start shooting
>more true micro. (Greater than 1:1)
>I have used close-up filters, Nikon T-series attachments, tubes, etc.
>All these are somewhat "Klutsy", and
>time consuming in the field. Has anybody
>ever seen, used, or even heard of a true
>micro lens that will go to like 6-1 or 10-1
>or whatever on it's own?
> Has such a lens ever been made? Is
>it possible to even design, let alone build
>one? Have seen much macro/micro
>discussion on the NG, but never any
>talk about such a lens.

If what you are asking for is a continuously focusable lens
that would go from infinity (or at least some moderate
magnification like 1/4X) into the higher magnification
ranges without additional accessories, the closest solutions
(since there are no ready-made lenses to do this) are a
lens of suitable FL on a bellows, or an easier-to-use
rig, a 1:1-focusing macro lens on a 2X converter with
an achromat on the front (this may get you only up to about
3X, but it does give some magnification adjustment capability,
and it retains the auto-diaphragm). Other issues: the combos,
even the best, will not go much above 3X sharply; the
higher-magnification combos will not offer much magnification
variability; and small stops are required for optimum sharpness
(TTL flash helps a lot here - look on my web page, under
"Bugs On The Run" for examples reaching about 3.5X using a
Nikkor 200mm f4 non-macro + converter + Sigma achromat,
a sharp combination at f11-16). If you want sharp results at
higher magnifications, you will need to give up versatility.
Specialized micro lenses are made by several manufacturers
which are optimized for narrow magnification ranges - you
buy the FL for the magnification range you want to cover.
These have no auto diaphragms, are generally used on bellows
or extension tubes, and their small screw mounts must be
adapted to your camera mount. They are very sharp at wider
stops (diffraction gets these, just as with any other lenses,
at small stops), and they are somewhat expensive (the Nikkor
versions are listed on my web page, under "I babble", along
with the other Nikkors for SLRs). BTW, a good substitute I
have found for a true micro lens is the 50mm f1.2 CRT
Nikkor - reversed (easy, using a BR2 ring) with the
correct extension to give about 5X magnification, is a
very sharp micro lens. These may still be available from
Brooklyn Camera for under about $150. High-magnification
macro work is, to put it mildly, difficult - DOF is
microscopic, focus must be exact, the working aperture is
small, vibration and subject movement are problems, ETC.
This is specialized work. Good luck!