Photoclubalpha

Sony A900
The A900, what a fine piece of camera!
It reminds me the Minolta XM for respect, seriousness, attention, meticulousness that one needs to devote to it when working out on the field. Noise? Noise is a pleasant looking film grain like pattern until 3200 ISO, at 6400 is not so good looking because seems, maybe... well... digital noise.

There is a review of A900 here from a very intelligent perspective I totally share:
http://theonlinephotographer.typepad.co ... 900-f.html

I have tested some lenses on my new A900 and so I post some note about.

Minolta AF 70-210 f/4 (the beercan)
This tele-zoom, with an optical design coming from Leica-Minolta collaboration era, is a true gem. It is surprisingly very sharp on A900, center to corner, at all focal legths and at 210mm too, even at f/4: at this aperture only vignetting is a visible issue. This is very impressive for a zoom.
A mention to the bokeh. The bokeh... is the best among the Minolta AF lenses I own, creamy and very smooth. I found beercan bokeh better than Minolta AF 100 f/2 or AF Apo Tele 300 f/4, at maximum aperture. I think this tele-zoom could be on pair with legendary MC Rokkor 58 f/1.2 I owned, talking about bokeh.
I loved very much the older manual version MD Zoom 70-210 f/4 and this AF version too on film.
But now I'm a little shocked, because on Sony A900 the beercan really shines.

positive factors:
- surprisingly very sharp at all focal lengths and apertures, for a zoom without APO specifications
- surprisingly beautiful bokeh
- useful in close-ups
- relatively fast lens but very portable yet
negative factors:
- there isn't a depth of field scale like the older manual version MD Zoom 70-210 f/4
- fiter mount rotates when focusing
- some CA visible at far edges at 210mm

Minolta AF APO D 100-300 f/4,5-5,6
- not so sharp like the beercan on corners at 100mm, even at f/16;
- very sharp from 200mm to 300mm at f11 and f16.
- smaller (or hardly visible) CA than beercan
- not so fast lens but very portable

Konica-Minolta AF D 28-75 f/2,8
- very very sharp at all focal length
- corner sharpness in pair with center f/11 to f/16
- very clean and crisp pictures
- relatively fast lens but very portable yet

Konica-Minolta AF D 17-35 f/2,8-4
- very sharp at all focal lengths
- corner sharpness at 17mm very good (but center a bit sharper) from f/11 to f/16, with very mild bluish CA.
- very clean and crisp pictures

Minolta AF D 24-105 f/3,5-4,5
- at 24mm: not so sharp on corners like the 17-35 f/2,8-4 at the same focal length, need f/16 to best corner to center sharpness, harder purple CA than 17-35 f/2,8-4 on corners;
- at 100mm not so sharp like the beercan on corners, need f/16 to best corner to center sharpness;
- sharp at others focal lengths at f/11 and f/16 (with corners worse, but a very little, than center), without CA issues.
- this little zoom isn't on pair with the other zooms in corners sharpness, at wide and at long end, but I'm seeing those differences at 100%; at normal print sizes, to see sharpness issues, must be careful, I think; in bigger sizes prints issues will be more visible.
- could be a good (not stellar, due to some little corners limitation) all-in-one, light, compact lens for travel, trekking, mountainering on Full Frame, until Sony will bring out some 24-105 G.


I haven't tested the lenses at greater apertures (except the beercan), because I'm more interested in shooting landscapes at f/11 and f/16 apertures. I will test and compare my prime lenses with zoom later.

Praise to Minolta for those strong perfomers!

NOTE.
I noted some lens needs a smaller aperture on A900 than on film camera, in order to reach the best center to corner sharpness, example f/16 on A900 instead of f/11 on Velvia. This could be explained, maybe, with better parallelism at smaller apertures of the light rays that arrive on sensor surface, in comparison to how much required by film surface?

Very interesting and very important, I would say.
Thank you very much.

Very good post & link is an interesting one.
Good to know what performs well going ahead.

Thanks, and a warm welcome to photoclubalpha

I would agree all round, having tested the same set of lenses. I decided to sell the 100-300mm and 24-105mm, despite not getting much for them really, as they were surplus to requirements. The only comment I would add is that the 24-105mm has very strong distortion (barrel at 24mm, pincushion at 105mm) which you don't mention. The 70-210mm is excellent for low distortion, the 28-75mm is also pretty good, and the 17-35mm is what you expect but no worse than any other similar lens even at twice the price.

This was my first reaction - that the Alpha 900 is exceptionally compatible with older Minolta lenses, in a way which some other full frame DSLRs have proved not to be with their own make's older lenses. We have been given an unexpected bonus.

David

Hello, David!
I'm happy that we have reached the same conclusions.

After tests, I think we can have a set of very good zoom lenses for our A900:

1. Konica-Minolta AF D 17-35 f/2,8-4.
2. Konica-Minolta AF D 28-75 f/2,8;
3. Minolta AF 70-210 f/4.

- The heavy (but typical in others similar lenses) distorsion issue on the Konica-Minolta AF D 17-35 f/2,8-4 at 17mm could be avoided, when framing the image, keeping off the sea horizon or the houses by edges, everywhere the trick is possible.
- The Minolta AF 17-35 f/3,5 is a pretty good lens, for a wideangle zoom, and is better on distorsion, but corners sharpness is so so and certainly not better than 17-35 f/2,8-4 especially at f/11 to f/22 apertures.
- An Italian monthly magazine "Tutti Fotografi" tested the Minolta AF 17-35 f/3,5 and the Tamron AF 17-35 f/2,8-4 (supposed the equivalent of Konica-MInolta) and some Canon L 16-35 and L 17-40.
- MTF graphics show the superiority at edges at f/11 to f/22 apertures of AF 17-35 f/2,8-4 versus AF 17-35 f/3,5. Canon Zooms are all not better than AF 17-35 f/2,8-4 in sharpness and distorsion at comparable focal lengths and apertures.
- In conclusion the Konica-Minolta AF D 17-35 f/2,8-4 is a very very good lens on A900, if one can face the limitations due to the distorsion issues at 17mm.


- I'm talking about landscape photography: often I must go in the mountains by foot and my trekkings take a lot of hours to reach locations. So, I need a ligther equipment, with a good focal range and at the same time pretty good.
- The Minolta AF D 24-105 f/3,5-4,5 and Minolta AF APO D 100-300 f/4,5-5,6 have more limitations and need small apertures in order to reach an acceptable sharpness at corners, not to mention distorsion issues on 24-105.
- Unfortunately, after test I see the needing to accept the issues of these lenses if I want to limit the weight of the equipment when weigth and compactness are important.

Has someone tested the Minolta AF 24-85 f/3,5-4,5 on A900? Are this one better than 24-105?