----- Original Message ----- From: "Shel Belinkoff"
Subject: RE: A Question About Macro Lenses
Try it yourself and then comment. I've done it and the differences don't
seem to be that great - hardly noticeable at all in some situations, not at
all in others. Camera was mounted on a Pentax macro copy stand, same
camera used, same film, and a refconverter used @ 2X to check focusing
accuracy.
While there may be some differences that become obvious at some point, they
were not obvious in a 5x7 print. I don't think the 100/2.8 macro in any
way "crushed" the K105/2.8 when the subject was a three dimensional object.
Results may be substantially different when photographing a two dimensional
object.
I had a small product job to do a while back that required about a 1/2 life size reproduction, but because of limitations on where I could set up, I ended up using the M150/3.5 on a tube, rather than the A100/2.8 macro.
In this application, the resulting chromes were just fine.
Presuming that you can't put a non macro lens onto a tube and shooting excellent quality close ups is a mistake.
Right now my slide copy rig is incorporating the 77mm lens, as it is the only focal length I have that I am able to make work with the istD and get full frame reproduction of the slide, using bellows and duplicator.
So far, I haven't seen any optical problems with this rig either.
Reproduction ratio would be about 2/3 life size, I expect.
William Robb
