To conclude the test that I started on this lens in May, I'll add a few more comments. The DOF scale is off slightly with the necessity of setting it more conservative by a half stop. A full stop different will yield 25 feet to infinity being quite sharp at f/32. I find the DOF for macro work not deep enough compared with the regular f/22 lenses. The difference between the 105 with tubes and the 135 with tubes is small. In macro work, the framing of the subject will be the same whether one is using a 90, 105, 135 or 150mm. Stand off distances will vary of course. So, this fact makes the focal ratio very important and the focal length not important as far as DOF is concerned in macros. The 135 does have better DOF than the f/22 lenses in macro work but not enough to be significant. I would like to see this lens with an f/45 stop, as it is badly needed, at least in my work. Overall, a good lens but it could be improved.

-- Steve Rasmussen (srasmuss@flash.net), January 26, 2002