Sony SAL 135 f/2.8 (T4.5) STF

Sony SAL 135mm f/2.8 (T4.5) STF

This is one of the lenses that Sony inherited from Minolta, re-branded and kept selling.
I am not sure how long will Sony keep this lens in production, because I doubt they have a big sales, and the profitability might be questionable too.

Is it a bad lens? No. It’s just not versatile enough for mass usage. This is a puristic portrait lens for 35mm full frame camera and it is designed and engineered to allow the smoothest possible rendering of out of focus areas, including transitions between high contrast and different colors, even if they are from the opposite side of the spectrum. 

Sony 135/2.8 is the only lens that I ever tried, with apodizing filter, or to be more precise – variable apodizing filter.

You might find better explanation on the web, what apodizing filter is and how it is affecting rendering, I will use a simplistic definition – this filter system (it’s variable) has graduated optical density coating, to soften light on the edges (refraction is diffused), while  keeping center optically neutral (uncoated). By moving filter within optical path, the intensity of softening is increase or decreased, at the similar way as it will be with a matte glass diffuser that will be moved from or closer to the light  source.

This solution have several consequences…

– It was invented and included in this lens optical design to make bokeh as smooth as possible.

– Diffusing in-coming light, also means however – reducing its intensity. Therefore, you will find that strange inscription on the lens 135/2.8 (T4.5). It means, that while physical size of the aperture correspond with the value of f/2.8, (allowing related DOF), the amount of light correspond to the value of f/4.5 (this is the exposure value that your camera will read when adjusting shutter speed or/and ISO). 

– The apodizing filter has circular shape, and in theory, the effect look best when your subject (in focus) is in the middle. In reality it doesn’t really matter.

To make long story short – this is not the lens that you will use to shot your running dogs, toddlers or dogs with toddlers. Neither cats.

This is the lens, that you will take on your first super-model shooting session, sponsored by one of the fashion designer icons. Or perfume designers.

The only other useful way to use this lens, will be to make this kind of borring blog tests, like I do.

Is it sharp at least? Oh, yes. But it is “just” f/2.8 lens remember? So it better be sharp for its price tag.

ISO 12333

Sony NEX 7 + Sony SAL 135f2.8 at f/4.5. Click for original.

Sony NEX 7 + Sony SAL 135f2.8 at f/5.6. Click for original.

Sony NEX 7 + Sony SAL 135f2.8 at f/8. Click for original.

Sony NEX 7 + Sony SAL 135f2.8 at f/11. Click for original.

Sony NEX 7 + Sony SAL 135f2.8 at f/22. Click for original.

Sony NEX 7 + Sony SAL 135f2.8 at f/32. Click for original.

Truth is, that you can achieve similar if not better resolution in the middle with many 135/2.8 lenses. But it is not all about MTF figures. We are perceiving  sharpness in context with surrounding, and that is where STF begins to show its uniqueness…

Bokeh Test

Sony NEX 7 + Sony SAL 135f2.8 at f/4.5 DOF is f/2.8

Sony NEX 7 + Sony SAL 135f2.8 at f/5.6

Portrait 1

Sony NEX 7 + Sony SAL 135f2.8 at f/4.5 DOF is f/2.8

Sony NEX 7 + Sony SAL 135f2.8 at f/5.6

Sony NEX 7 + Sony SAL 135f2.8. Center crops. Click for original.

Portrait 2

Sony NEX 7 + Sony SAL 135f2.8 at f/4.5 DOF is f/2.8

Sony NEX 7 + Sony SAL 135f2.8 at f/5.6

Sony NEX 7 + Sony SAL 135f2.8. Center crops. Click for original

Portrait 3

Sony NEX 7 + Sony SAL 135f2.8 at f/4.5 DOF is f/2.8

Sony NEX 7 + Sony SAL 135f2.8 at f/5.6

Sony NEX 7 + Sony SAL 135f2.8. Center crops. Click for original.

Sony NEX 7 + Sony SAL 135f2.8 at f/4.5 DOF is f/2.8

Sony NEX 7 + Sony SAL 135f2.8 at f/4.5 DOF is f/2.8

Sony NEX 7 + Sony SAL 135f2.8 at f/4.5 DOF is f/2.8

Sony NEX 7 + Sony SAL 135f2.8 at f/4.5 DOF is f/2.8

Sony NEX 7 + Sony SAL 135f2.8 at f/4.5 DOF is f/2.8

Sony NEX 7 + Sony SAL 135f2.8 at f/4.5 DOF is f/2.8

Links to the other 135 reviews (in progress):

Olympus E. Zuiko Auto-T 135mm f/2.8
Sony SAL 135/1.8 Zeiss Sonnar T* ZA
Carl Zeiss Sonnar 135mm f/2.8 T* (C/Y)
Canon EF 135/2 L USM
Minolta MC Rokkor-PF 135/2.8