[wim]

It's the kind of questionable AF consistency usually associated (in the Internet-speak at least) with the Sigma lenses. I have to admit that I abuse my 24 pretty badly - like I do with all fast primes - by employing them in the very difficult lighting conditions. Still, the Tamrons 45mm and 85mm are more consistent than the Sigma 14mm and Canon 24mm in my opinion, although these two are not outright bad - they just go off the deep end sometimes, rather unpredictably.

Still it was mighty fun shooting the celebrations of the Buddhist New Year last night with 2 cameras and these 4 primes. I might have looked like a prime-snob though.

Impossible!
There is no such things as a prime snob, except when shooting with fast Leica primes

Yeah, and someone as... spirited would probably never be caught alive using an APS-C camera, it'd be a sacrilege.

Phew! Wiping brow ... That is not me in that case, even worse than APS-C that I carry around besides FF: MFT!

Kind regards, WIm

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Based on what I can see under lab conditions, it is a valid sample.

Brace for an "interesting" rating ...

Just to get back to this, after an, IMO, interesting realization:
When you look at the comparison of jpegs vs RAWs, it is obvious that the jpegs are slightly cropped, actually.

I am now wondering whether the sensor sees more than 24 mm at the wide end or not, and if so, whether the jpegs actually show an AoV that is conform what you would expect for 24 mm on FF or not.
Basically, the worst of the dark corners are actually cropped away with jpegs, and the last little remainder is corrected away, with corrections on.

Kind regards, Wim

24mm is 24mm.... Uncorrected one would call it "fisheye", and will have a wider FOV than corrected. If you correct barrel distortion, you crop "the corners" and end up with 24mm corrected FOV.

No, it is not a fisheye. Neither is the barrel distortion all that bad.
Have you actually shot with any of these lenses - I actually have.

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It would be interesting to see an FOV comparison to determine which lens gives wider/narrower angle. Of course, then focus breathing might also come into play.

Is it really possible to have a "measuring stick" lens for a given FL (24mm in this case), anyway? One that can be declared the one to give a true 24mm FOV?

I have always hated the discussion about focus breathing. Although this is a fine trait for video, it actually mean sthat teh FL is decreasign when focusing more closely.
I have never considered it a great treat for stills, or, IOW, photography.

Somebody started throwing aroudn this term at soem stage, and somehow a lot of people forgot that there really is a big difference between stills photography and video or filming.
I really hate it when you start at 200 mm far away, and end up with 135 mm in close-up.

Kind regards, Wim

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It would be interesting to see an FOV comparison to determine which lens gives wider/narrower angle. Of course, then focus breathing might also come into play.

Is it really possible to have a "measuring stick" lens for a given FL (24mm in this case), anyway? One that can be declared the one to give a true 24mm FOV?

Is it really possible to have a "measuring stick" lens for a given FL (24mm in this case), anyway? One that can be declared the one to give a true 24mm FOV?

Lenses designed primarily for still photography almost universally suffer from focus breathing. Convention would dictate that the nominal focal length would be at infinity focus.
It follows that, since most lenses breathe to some degree, exact focal length is rather academic - more so in zoom lenses.

True Cine lenses are a different kettle of fish.

Focus breathing is a load of crap, or nonsense, IMO.
A lens created to prevent focus breathing, which happens to be a totally nonsensical term, effectively means that it shortens it FL when focusing closer.
It is something I have hated for stills photography whenever it was applied, and it with macro lenses it gets even worse, because it means that you are left with less space between your subject and your setup - the FL is shorter after all.

It should have been called focal shortening upon focusing, or something like that, because that is what it really is.

In zoom lenses it is a lot worse, i.e., focal shortening, because of the inherent design compromises that are made. Funnily enough, a few years ago a lot of fuzz was made of zoom lenses that shortened FL when focusing closer. I remember the discussions about the Nikon 70-200, with the 200 mm end becoming 135 mm at shortest focusing distance, vs the Canon 70-200, which stayed around the 190-195 mm mark or thereabouts. Nowadays it is acceptable, because it means it suffers less from "focal breathing".

Why is that an issue at all, with stills photography? Or even with video for that matter, as in the olden days nobody was bothered by it. To me, "focal breathing" looks good, because it shows that you are getting in close-up. The movement that "focus breathing" causes, makes it intrinsically clear that you are gettign closer. But maybe that is just old-fashioned me.

Kind regards, Wim

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Is it really possible to have a "measuring stick" lens for a given FL (24mm in this case), anyway? One that can be declared the one to give a true 24mm FOV?

Lenses designed primarily for still photography almost universally suffer from focus breathing. Convention would dictate that the nominal focal length would be at infinity focus.
It follows that, since most lenses breathe to some degree, exact focal length is rather academic - more so in zoom lenses.

True Cine lenses are a different kettle of fish.

IMO still photography lenses which are designed properly do not suffer at all from anything, They have the great ability to not have any FL shortening when focusing closer, unlike most modern zoom lenses, or CINE lenses ....

Kind regards, Wim