> Using the A100/2.8 macro and the K105/2.8 on the same subject, > there didn't seem to be any observable difference between the two > photos. Under what circumstances would a macro lens be the better > choice, and when might an ordinary lens be a better option?
I really like the A 100/2.8 Macro a lot (one of my favorite lenses). I also used to own the K 105/2.8 (at the same time as I owned the A 100/2.8 Macro). I pack the 100/2.8 Macro for almost any outing, whereas I almost never packed the K 105/2.8. The 100/2.8 Macro let me shoot almost anything that I wanted (using a lens in the 100-ish range), close or far, while the K lens could not focus too close. The maximum apertures were the same. Bokeh (important to me) may not be the best feature of the 100/2.8 Macro, but it certainly is not for the 105/2.8, either. So, in answer to your question, Shel, specifically referring to these two lenses, I'd say that - for me - the A 100/2.8 Macro would ~always~ be the better choice - <g>. Fred
