In dealing with the Sigma 28-105 lenses, remember that there is the 28-105 4-5.6 UC, the 28-105 4-5.6 UC II, and the just-released 28-105 3.8-5.6 UC III, as well as the 28-105 2.8-4. According to the test results, each new version of the 4-5.6 UC make was better than the last. I have the latest… Read More »
It is usually rated as one of the top in it’s class. But a better question is, how much production variation exists between lenses of the same make and model? If you took 100 different 85mm f/1.4 lenses and ran the same tests for, say, resolution (lines per mm) under controlled conditions, how much would… Read More »
I’m sure I’ve mentioned this before. An adaptor exists. It has a piece of glass in it, kind of like a teleconverter. Why? If you’ve ever used extension tubes (which are great, by the way!) you would notice that when the lens gets further away from the camera, the focal plane gets closer to the… Read More »
The last time I heard of one of those, it was a case of an early Sigma lens that only worked with the first series of Minolta AF cameras (7000 and 9000) but was software incompatible with the later versions. In addition to manual focus, you could only shoot with aperture wide open, because the… Read More »
I had written earlier that Sigma’s 24mm f/2.8 autofocus lens was sharper than Minolta’s, relying on, among others, photodo.com’s tests. Someone (I forget who) corrected me, saying that while Sigma was sharper at the center, Minolta was sharper at the edges. I went back to photodo.com and checked the two. Looking carefully at every single… Read More »
The two you mention are the sharpest pieces of glass Minolta sells! Remember as you get into the lower focal lengths that it becomes more difficult for a manufacturer to make a lens of the same sharpness as 50 or even 100mm. That aside, the 35mm f/2.0 and the 35mm 1.4 are both almost as… Read More »