100% crops from the mid-field of the A900, all lenses wide open. One might think that some of the crops are out-of-focus, but the corresponding center of the images proves that they were all correctly focused. See inside for details.

In an earlier test (Details see here) the Zeiss ZA 2.8/16-35mm proved to be clearly superior to its counterparts Minolta 3.5/17-35mm G and Minolta 2.8-4/17-35mm (D). While at 17mm/2.8 the Zeiss was really shining.

In this little test the 16-35mm Zeiss was compared to three classical Minolta designs: the Sony 1.4/35mm G, the Minolta 2/35mm and the Minolta 4-4.5/28-135mm. While the two latter lenses generally have a very high reputation, the 1.4/35mm doesn't shine in common tests (such as this one). Due to its special tone rendering, and its very shallow depth-of -field wide open, it produces quite special results. I will comment on this in a (soon-to-come) separate entry on the 1.4/35mm.

When I was examinig the results on my computer I was quite astonished. I certainly had expected that the Zeiss would beat at least one of the three Minolta designs (all of them basically dating from the mid-80's of the last century).

It doesn't.

COMPARISON ON BOKEH WILL FOLLOW SOON, AS WELL AS A COMPARISON OF THE ZEISS ZA 2.8/16-35MM WITH MINOLTA AF 2.8/20MM, AF 2.8/24MM, AND AF 2.8/28MM

Sony alpha 900, Manfrotto 055C tripod with Manfrott 410 three way head, mirror lock up (2s), remote cable.

All lenses AF-calibrated (Micro AF for maximal resolution in the center).

RAW files converted with Adobe Photoshop CS3 (sharpening: amount 50, radius 0.5 px, detail 50). No correction of CAs and lens vignetting, no de-fringing.

The effective focal lengths of the lenses are differing. In the center at f=35mm the Zeiss 2.8/16-35mm is 5% shorter than the Minolta 2/35mm; therefore for some lenses the "corner" crop is not exactly in the corner (mainly the Zeiss).

TEXT

	In the center and the extreme corners the detail resolution is suprisingly good, but in between there is a pronounced "valley", probably caused by field curvature. Contrast is quite low, similar to the other two Minolta f1.4 lenses (namely the Minolta 1.4/50mm and the Minolta 1.4/85mm) CAs are quite pronounced as well, but they can be easily corrected using any of the well known RAW convertes. Vignetting is surprisingly low even on the full-frame A900. Focusing at f1.4 was quite challenging since the lens has (in addition to the field curvature) also an f-stop error and other aberrartions. As you can see on the upper left window the lens is slightly back-focused at f1.4 (red longitudinal CAs), but it becoms front-fucused when stopping down to f2 (green longitudinal CAs, see below).
	At f2.0 there's slightly more detail in the center, a slightly better contrast, and clearly less vignetting.
	Even wide open the small Minolta 2/35mm clearly outperforms the much more expensive 1.4/35mm. Resolution and contrast are much better, especially in the mid-field, and there are virtually no CAs. I heard from Sony representatives that some of the Minolta legacy lenses can't be manufactured again due to missing glass (environmental issues, e. g. lead-containing glass???). The much appreciated 2/35mm seems to be among these lenses. What a pity!

TEXT

	At f2.8 the 1.4/35mm improves, but still is far from it's optimal aperture. Center resolution and contrast, however, are perfect now. Vignetting has become very low, and bokeh is at its best. CAs are still (too) pronounced, but can be corrected.
	Stopped down to f2.8 the Minolta 2/35mm has less vignetting, otherwise it remains quite similar as at f2.
	What a surprise, and not a nice one. While center resolution and contrast are nearly as good as a prime, the corner are nothing but ugly. Even the mid-field is quite bad. First I thought that this was faulty copy, but looking at the MTFs published by Sony I dicovered that this performance seems to be normal.
	Again, the 25 years old Minolta AF 4-4.5/28-135mm shines. Wide open (at f4) its corner and midfield resolution is superior to both primes and the Zeiss at f5.6. Remarkable indeed.

TEXT

	Finally, at f5.6, the performance of the 1.4/35mm becomes even. CAs are still quite strong.
	At f5.6 the Minolta 2/35mm is still slightly better than the 1.4/35mm (less CAs)
	At f5.6 the Zeiss becomes acceptable, but not stellar at all.
	Stoped down to f5.6 the 28-135mm has more contrast, but seems to loose some detail resolution.

TEXT

	Finally, at f11, the Zeiss 2.8/16-35mm delivers top results with virtually no CAs (close to the 2/35mm at f5.6).