After one month of thorough shooting and lens testing with my a900 I feel it's time to summarize my experience with different Minolta / Sony / Zeiss lenses.

1/2009: UPDATED WITH INFORMATION ON MANY CLASSICAL MINOLTA ZOOMS AND THE SONY 70-300MM SSM G

Minolta AF 20mm 1:2.8 Quite sharp wide open (f2.8), but very pronounced vignetting and very low contrast in the corners. Detail resolution and contrast becomes very good (also in the corners!) when stopping down to f8 ... f11. Vignetting is no problem any more at f8. RECOMMENDED FOR THE USE WITH THE ALPHA 900

Minolta AF 24mm 1:2.8 Not as sharp as the 2.8/20mm, but at f 2.8 also very pronounced vignetting and very low contrast in the corners. When stopping down to f11 the detail resolution and the contrast become very good in the center and in the corners.Vignetting is no problem any more at f8.

Minolta AF 28mm 1:2.8 Considerably less convincing than the 20mm and the 24mm. Some problems in the corners remain even at f11.

Sony 35mm 1:1.4 (PRELIMINARY) At f1.4: Quite low contrast, yet surprisingly good detail resolution even in the corners. Stopping down increases continually. Between f2 and f4 the MinAF 2/35mm is better! At f8 simply perfect detail resolution & contrast even in the extreme corners - probably better than the Zeiss 16-35mm and Zeiss 24-70mm. Strong longitudinal CAs, weak lateral CAs (MinAF 2/35mm is much better!). Depending on the distance, bokeh can be "noisy" at f1.4, but becomes very good at f2.8.

Minolta AF 35mm 1:2.0 While almost perfect on 80% of the FF area, the corners are not satisfying wide open (f2.0). Stopping down to f4 ... 5.6 increases the corners to very good levels, and for perfect performance f8 ... 11 is recommended. RECOMMENDED FOR THE USE WITH THE ALPHA 900

Minolta AF 50mm 1:1.4 Very low contrast, but lots of details at f1.4. Gradually increasing contrast - starting from the centre af f2.0 and reaching its optimum at f4.0 (centre) and f8 (corners). Extremely sharp (detail resolution) at f5.6 ... f11. RECOMMENDED FOR THE USE WITH THE ALPHA 900

Minolta AF 85mm 1:1.4 (PRELIMINARY) Again very low contrast, but lots of details at f1.4. Gradually increasing contrast - starting from the centre af f2.0 and reaching its optimum at f4.0 (centre) and f5.6 (corners). Extremely sharp (perfect detail resolution!) and very good contrast at f4.5 ... f11. RECOMMENDED FOR THE USE WITH THE ALPHA 900

Minolta AF 100mm 1:2.0 At f2.0: Perfect detail resolution and good contrast from centre to the corners wide open, vignetting well controlled. Contrast slightly increasing at f2.8 ... f4; vingetting disappears at f4. Virtually no lateral CAs. Some longitudinal CAs at f 2.0; disappearing from f2.8 onwards. CLEARLY RECOMMENDED FOR THE USE WITH THE ALPHA 900, EVEN WIDE OPEN

Minolta AF 100mm 1:2.8 Macro At f2.8: Excellent center resolution / contrast, corners very good. Some vignetting in the corners. At f 5.6 and f8: excellent detail resolution and contrast even in the extreme corners. Little vignetting at f5.8, virtually no vignetting at f8. CLEARLY RECOMMENDED FOR THE USE WITH THE ALPHA 900

Sony SAL 135mm 1:2.8 [T4.5] STF (PRELIMINARY) Perfect detail resolution, perfect contrast, and perfect bokeh wide open. Stopping down just deteriorates the bokeh. CLEARLY RECOMMENDED FOR THE USE WITH THE ALPHA 900

Minolta AF 135mm 1:2.8 (PRELIMINARY) Very good (but not excellent) detail resolution and contrast wide open; increases when stopping down to f4.

Minolta AF 200mm 1:2.8 APO HS Excellent detail resolution and very good contrast wide open (f2.8), even in the extreme corners. Stopping down to f4.5 slightly increases the contrast. No visible CAs. Some vingetting at f2.8, disappears at f4. The lens is almost perfect. CLEARLY RECOMMENDED FOR THE USE WITH THE ALPHA 900, EVEN WIDE OPEN

Minolta AF 300mm 1:2.8 APO HS Center: Very good detail resolution and contrast wide open; excellent when stopping down to f5.6. Corners: Good - very good at f2.8, very good - excellent at f5.6 and f8. f11 slightly deteriorates the overall image quality. Some vignetting at f2.8, completely gone at f8. RECOMMENDED FOR THE USE WITH THE ALPHA 900

Minolta AF 3.5/17-35mm G Very well built, design fits perfectly to the a900. Very sharp and very good contrast in the center, even wide open. Corners not very sharp. Vignetting pronounced wide open, but acceptable from 5.6 on.

Minolta AF 2.8-4/17-35mm Very sharp and very good contrast in the center, even wide open. Corners at 17mm/2.8 EXTREMELY bad, lens is useful from 20mm on. Quite good corner details at 20mm/f11 (better than the G). Vignetting pronounced wide open, but acceptable from 5.6 on.

Minolta AF 4/24-50mm while excellent at the APS-C alpha 700, this lens has the similar corner problems as the above mentioned lenses on the alpha 900.

Minolta AF 2.8/28-70mm G Very well built, design fits perfectly to the a900. Over the entire range of apertures not really razor sharp (clearly less detail resolution than the Minolta 4-4.5/28-135mm and the Zeiss 2.8/24-70mm). Some corner problems (comparable to the Zeiss 2.8/24-70mm and the 2.8/70-200mm APO G SSM at f=70mm), but remarkably little CAs (at 70mm less than the Zeiss 2.8/24-70mm).

Minolta AF 3.5-4.5/28-85mm (INFORMATION WILL FOLLOW)

Minolta AF 4-4.5/28-135mm (70mm) Very good detail resolution when stopped down to f8, even in the corners (better than the Zeiss 2.8/24-70mm), and over the entire range of focal lengths. Comparable to primes. Wide open good detail resolution, but lower contrast. Vignetting is well controlled and disappears at f8. (100mm) Perfect detail resolution in the center even wide open, no improvement when stopping down to f8. Extreme corners very good wide open (comparable to Sony 2.8/100mm Macro at f2.8!) and perfect at f8. Very little vignetting wide open, virtually no vignetting at f8. Detail resolution at 100mm/f8 comparable to the excellent MinAF 2.0/100mm and MinAF 2.8/100mm Macro, but more prone to flares. CLEARLY RECOMMENDED FOR THE USE WITH THE ALPHA 900

Minolta AF 4/35-70mm (INFORMATION WILL FOLLOW)

Minolta AF 3.5-4.5/35-105mm (100mm) Center very good even wide open, no improvement when stopping down. Corners quite soft, not much improvement at f8. Vignetting is well controlled even wide open. A second copy tested had the same probelms - therefore: Not exactly a great performer on the alpha 900.

Minolta AF 2.8/70-200mm APO G SSM Very well built (yet not as "tank-like" as the white Minolta 2.8/80-200mm APO HS); excellent center resolution wide open even at f=200mm, corners slightly softer (less detail resolution than 2.8/200mm APO @ f2.8). Some improvement when stopping down to f4.5 (at f4.5 the 2.8/200mm APO is truly excellent; the SSM doesn't reach this level). But be aware: at 200mm the corners of the 2.8/70-200mm SSM wide open (f2.8) are better than the corners of the venerable 4/70-210mm ("beercan") at f8 ... At f=200mm virtually no CA's, but visible CA's at f=70mm.

Minolta AF 4/70-210mm "beercan" (100mm) Center very good even wide open, no improvement when stopping down. Corners are good at f4, and excellent at f8. No CAs at all. Vignetting is visible at f4, but gone at f8. Very good performance. (200mm) Center resolution satisfying (but not very good) wide open; very good at f5.6 and excellent at f8. Corners OK wide open, good at f8. Clearly visible CAs. Strong "spot-like" vignetting wide open, vignetting gone at f8.

Sony SAL 4.5-5.6/70-300mm SSM G (100mm) Perfect detail resolution and contrast in the center; stopping down to f8 slightly decreases (!) the detail resolution. Corners are a bit soft wide open, and very good at f8. Corners at f4.5 are worse than the 2.8/80-200mm at f2.8, and comparable to the 70-210mm at f4. Very good, but not excellent performance. (200mm) Simply excellent detail resolution and contrast at f5.6, no improvement when stopping down to f8. Corners have a very good detail resolution even wide open, and are truly excellent at f8 (comparable only to the 2.8/200mm APO). No CAs at all. Vignetting well controlled at f5.6, and virtually disappearing at f8. (300mm) Center resolution is excellent even wide open, but corners are surprisingly weak wide open (comparable to 4/70-210mm at visibly better the "big beercan", and much better than the legendary 4/70-210mm "beercan" - especially at 200mm the improvement is quite dramatic!

Minolta AF 4.5-5.6/75-300mm "big beercan" (100mm) Center good - very good wide open, very good when stopping down. Corners are OK at f4.5, and good - very good at f8. No CAs at all. Slightly worse than the MinAF 4/70-210mm. Little vignetting at f4, and gone at f8. (200mm) Center quite soft and somewhat low contrast wide open (f5.6), but excellent at f8. Corners quite soft as well at f5.6, but very good at f8. Less vignetting and less CAs than the MinAF 4/70-210mm. (300mm) The center is quite soft wide open, good at f8, and very good at f11. The corners are very similar - a quite even performance over the entire image field. Relatively little CAs (less than the 4/70-210mm at f=200mm!). Strong spot-like vignetting wide open, but already at f8 it's almost gone. At 100mm slightly worse than the beercan (4/70-210mm), but at 200mm clearly better.

Minolta AF 2.8/80-200mm APO (100mm) Center and corners are excellent even at f2.8, only slightest improvements when stopping down to f5.6. Little vignetting at f2.8, disappears at f5.6. Overall performance at f2.8 slightly better than the Sony 2.8/100mm Macro! Focal lenghts between 80mm and 135mm are very well corrected (I would say even slightly better than the 70-200mm SSM, but that's just my impression, e. g. less CA's). (200mm) At f2.8 the lens is very good in the center. Stopping down to f4.5 increases center resolution to excellent levels, while corners need f8 for excellent detail resolution. Strong vignetting at f2.8, reduced at f4 - 5.6, disappearing at f8. At f8 similar overall performance as the 2.8/200mm APO at f2.8 ... and clearly visible CAs.

Minolta AF 4.5/100-200mm "small beercan" (100mm) Center has a good-very good detail resolution wide open, but the contrast is quite low. Very good resolution at f8. Corners are very good at f8, and there are simply no CAs. Quite strong vignetting wide open (f4.5), still a little bit at f 8. (200mm) Center very good wide open and stopped down, corners quite soft (similar to 4/70-210mm). Less CAs than 4/70-210mm. Strong vignetting at f4.5, doesn't really disappear even at f8.