T3D Re: TECH-3D digest 382

[Eric Goldstein <egoldste@xxxxxx>]

> Dave Spacey wrote:
> 
> > ...are you using a reversing ring?

and John B replys:

> I hadn't look at that sort of magnification before getting my macro
> lenses so the answer to that is "no".  I would have thought you would
> have to have very large magnifications if you use a reversing ring.
> But I've certainly never tried it.

John is correct, reversing rings yield magnifications which are
typically greater than those practical for our purposes, and of course
the lens to subject distances are quite small. Also, some lens designs
do not yield better performance when reversed, so YMMV...

Andrea talks about her 100 mm macro lens with a minimum aperture of
f/32. I'd just point out that the DOF here is comparable to a 50 mm lens
at f/16, so the only advantage is an increased lens-to subject distance.

>From my own experience I would highly recommend doing one's first macro
work with your trusty 50 mm prime lens at f/22 (the 100 mm macro would
need f/45 for the same DOF!) and an inexpensive set of auto extension
tubes (I found mine in FD mount on rec.photo.marketplace for $30). With
a good steady tripod and slide bar and careful attention to lighting and
background, you will be astonished with the results!


Eric G.


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