Sony 100mm f/2.8 STF GM - what's its purpose?

[Slobodan Blagojevic]

Rob,

Those girls do not need Hans or 300mm to look amazing.

Given how skinny models are, telephoto flattening (and fattening) of their faces can only do them a favor.

100mm is considered the most natural for head and shoulders portraits, especially if hands are involved. By most natural, it is meant as the proportion of hands, nose, etc. size to face. Shorter than that, say 50mm, makes hands larger than face, and the nose more prominent, for instance. But what do I know, I only read about it, with visual examples, in Modern/Popular Photography, penned by Herbert Kepler, if I am not mistaken.

On a personal note, when I shoot my daughter full-face at 200-300mm, she wants to shoot me: it makes her face fat and flat.

[Rob C]

C'mon, Slobodan, don't use the girls as justification; not all face models are stick insects.

Regarding the definition of portrait, I speak of headshots, you of half-lengths; this could become crazier than Brexit debates, but I'm not going there. I rest on what I know and did.

Fell free to shot however you desire.

:-)

[Kirk_C]

As with so much in photography, it boils down to lighting, model, focal length/format combination and a sound understanding of your own intentions.

That's where these dry discussions can go awry: photographic reality isn't actually that bound by theoretical certainties, but by trial and error.

Well said.

I've shot many a model that enjoyed the benefit of a longer lens and they weren't all thin.

[Slobodan Blagojevic]

Jesus, people, you act like some offended primadonas. 

[KLaban]

Rob,

Those girls do not need Hans or 300mm to look amazing.

Given how skinny models are, telephoto flattening (and fattening) of their faces can only do them a favor.

100mm is considered the most natural for head and shoulders portraits, especially if hands are involved. By most natural, it is meant as the proportion of hands, nose, etc. size to face. Shorter than that, say 50mm, makes hands larger than face, and the nose more prominent, for instance. But what do I know, I only read about it, with visual examples, in Modern/Popular Photography, penned by Herbert Kepler, if I am not mistaken.

On a personal note, when I shoot my daughter full-face at 200-300mm, she wants to shoot me: it makes her face fat and flat.

Jesus, people, you act like some offended primadonas.

When everybody thinks the same...nobody thinks.

;-)

[Rob C]

Jesus, people, you act like some offended primadonas.

I missed the link and/or deleted posts: whither and who the 80s "top models" who took umbrage?

:-)

Rob

[Herbc]

any similarity with Nikon's DC nikkor lenses? They are AF as well.

[Jim Kasson]

any similarity with Nikon's DC nikkor lenses? They are AF as well.

No.

https://blog.kasson.com/the-last-word/bokeh-can-you-see-greatly-defocused-images/

Jim

[Kirk_C]

https://blog.kasson.com/the-last-word/bokeh-can-you-see-greatly-defocused-images/

Thank you, that's useful.

It also demonstrates (to me) the OP's opinion that the STF feature is better suited to a longer than 100mm focal length.

[Paulo Bizarro]

IMO it is pointless to discuss "what lens is better for portraits", because it depends on the type of portraits one wishes to produce. Perhaps Sony chose 100mm for STF lens because of compromises related to: price, size, weight, AF, OSS, anything more?

A future FE 135 f1.8 (or f2) lens is bound to happen, which will be kind of big and heavy. Even Zeiss chose to compromise on the Batis 135, making it f2.8; and for sure they could have done it f2, increasing in size and weight.

The point still remains that an STF lens is a specialized lens, and the Sony 100mm one takes nice portraits, and is excellent at close ups too.

[shadowblade]

The point is, if you're going to go to the trouble of putting STF in a lens (and making it much more specialised than the same lens without STF - the two stops of light loss cuts down its utility in other situations), why not put it in a lens where the STF element really enhances the strength of the lens, by making it even better for the tasks it's already good for? Putting STF in a 100/2.8 lens is just like making an entry-level 18-55mm zoom with tank-like build and weather sealing or a 16-35/2.8 UWA with an inbuilt 1.4x TC - yes, each of those would make the lens technically 'better' and more capale, at the expense of something else (light transmission for the 100/2.8, weight and cost for the entry-level zoom and the UWA) but hardly plays to the strength and purpose of each lens.

STF would be great as a toggle element in a supertele for wildlife photography (like inbuilt 1.4x TCs). When shooting wildlife, you often have little control over the background (the animal is where it is, and you can't move it) and you often encounter distracting background elements which need to be blurred out - grass, leaves, branches, reflections from ripples on water, all of which frequently produce distracting or harsh backgrounds even on lenses with good bokeh. You could use the STF in good light to eliminate this problem, while switching it out in bad light (or just sucking up the 1-2 stops of increased ISO - it's not like either the A9 or A7r3 are lacking in high-ISO capability).

[Paulo Bizarro]

The point is, if you're going to go to the trouble of putting STF in a lens (and making it much more specialised than the same lens without STF - the two stops of light loss cuts down its utility in other situations), why not put it in a lens where the STF element really enhances the strength of the lens, by making it even better for the tasks it's already good for? Putting STF in a 100/2.8 lens is just like making an entry-level 18-55mm zoom with tank-like build and weather sealing or a 16-35/2.8 UWA with an inbuilt 1.4x TC - yes, each of those would make the lens technically 'better' and more capale, at the expense of something else (light transmission for the 100/2.8, weight and cost for the entry-level zoom and the UWA) but hardly plays to the strength and purpose of each lens.

STF would be great as a toggle element in a supertele for wildlife photography (like inbuilt 1.4x TCs). When shooting wildlife, you often have little control over the background (the animal is where it is, and you can't move it) and you often encounter distracting background elements which need to be blurred out - grass, leaves, branches, reflections from ripples on water, all of which frequently produce distracting or harsh backgrounds even on lenses with good bokeh. You could use the STF in good light to eliminate this problem, while switching it out in bad light (or just sucking up the 1-2 stops of increased ISO - it's not like either the A9 or A7r3 are lacking in high-ISO capability).

In your OP, you asked for other thoughts. I have offered mine. That is all, nothing more. As I said, Sony chose to make a specialized STF lens that excels at portraits, with the bonus of =0.25X magnification for say nature flower shots with special quality background blur.

If you have no applications for it, others shave.