This fast prime lens is quite old (Minolta beercan era : 1985), and is reasonably priced on the after market (200€). it is very compact and lighweight and the autofocus speed is very fast. Is it the perfect complement of my Tamron 17-50 f2.8 ?

My favorite lens for portraiture was the M42 Jupiter 37A (135mm f3.5) because of it's wonderfull image quality and because I like this focal lenght for portraiture on APS-C sensors. The only drawback is the manual focus. So I decided to look for the equivalent prime lens but featuring autofocus. The older AF Minolta lenses are the beercan era ones (1985).

Presentation and built quality:

The Minolta AF 135 is part of this famous beercan familly.

It is all metal built.

The most intersting feature is it's compactness : when mounted on my Sony A700, it is so small that nobody will figure out that you have got a 135mm tele !

This is a great avantage for stealing shots or for candids!

Thanks to it's compactness, it is not heavy at all despite it is all metal built : 365g.

The manual focus ring is very narrow.

The Minolta AF 135 F 2.8 feature a built in lens hood :

The minimum focusing distance is 1000mm.

The filter diameter is 55mm

Operation & focus speed:

Beercam era zoom are slow to focus in low light ans sometime hunts. This is not the case with this prime lens.

The autofocus speed is excellent even in low light condition. I was not expecting a 25 years old 135mm tele to be so fast and accurate. As a consequence it is a perfect lens for weddings or indoor shooting without flash. It behave the same as the Minolta AF 50 f1.7.

It makes a big difference with the Minolta 70-210 f4 or the Minolta 35-105 old which do not like low light conditions.

Compared with my best lens the Jupiter 37A (135mm F3.5), the Minolta is slighly faster : f2.8 instead of f3.5

In lowlight it may prevent you from using to high ISO setting and avoid some noise. Or it can helps to abstract the subject from the context with a narrower deep of field

Image Quality:

To be clear, compared with my best lens the Jupiter 37A (135mm F3.5), the Minolta image quality is disapointing. Because I was expecting the autofocus prime to be better than the very old russian manual focus one.

It is not the case but the Minolta produce very good results.

Considering sharpness, it is really usable @f2.8 (I would say the same sharpness as the 70-210 beercan @f4.0)

When stopped down @f3.5 it is very sharp.

The colors are superb typicaly Minolta.

The bokeh is very soft:

The main issue with this prime lens is the amout of purple fringing when used front of the sun @f2.8 even with the hood extended (useless in this condition)

Conclusion

Surprinsingly, even if the image quality is not as good as the one produced by the Jupiter 37A, the Minolta AF 135 f2.8 is one of my favorite lenses because it is the perfect complement with my tamron 17-50 f2.8.

I like it's compactness, it's fast fast focus speed and the image quality it produces.