[stoppingdown]

With some samples (not many macros that I'd like to see):

https://sonyalpha.blog/2019/12/04/tamron-24mm-f2-8-di-iii-osd-m-12-f051/

It looks like the only defect is distortion (and noisy AF for those who does video recording).

[Juli1a]

First is the very strong distortion which needs to be corrected for many images liteblue.

[Klaus]

I'm slightly wondering whether those 3 Tamron lenses are really so interesting. These are all f/2.8s after all.
The 20mm is, IMHO, the most useful of three. The other two ...

[Brightcolours]

I'm slightly wondering whether those 3 Tamron lenses are really so interesting. These are all f/2.8s after all.
The 20mm is, IMHO, the most useful of three. The other two ...

You are correct in that they are only f2.8, and as such would also be covered by f2.8 standard zooms.

However, there is only the Sony E 16-55mm f2.8 G, which is pricy (€1300) and pretty heavy (~500 grams). And that lens only achieves 1:5 magnification, where these Tamron lenses' USP is their 1:2 macro ability.

That makes 3 arguments for the Tamron f2.8 primes.

1. 1:2 max. magnification ability
   
2. comparatively low price
   
3. quite a bit more compact and light than the standard zoom alternative
   

One of my favourite images I have taken on APS-C was with 35mm at 1:2, so I can see the interest of these lenses for the niche audience that likes wider angles close ups upto 1:2. And of course, they do also do infinity stuff, besides the 1:2 ability.

Taken with a 35mm at 1:2, vertical images stitched., shot with Canon APS-C.
The FF equivalent to 35mm on Canon APS-C is 56mm. 

Also shooting with a 55mm 1:2 (max. magnification) lens on FF I can appreciate these Tamron 1:2 APS-C offerings.... The choice of FOV matters for the outcome, also at close up and macro ranges.


Taken on FF with a Nikkor 55mm f3.5 micro.
So if my platform would be Sony APS-C, I would be quite interested in this Tamron trio, due to their close up ability.

[JJ_SO]

I'm slightly wondering whether those 3 Tamron lenses are really so interesting. These are all f/2.8s after all.
The 20mm is, IMHO, the most useful of three. The other two ...

You are correct in that they are only f2.8, and as such would also be covered by f2.8 standard zooms.

However, there is only the Sony E 16-55mm f2.8 G, which is pricy (€1300) and pretty heavy (~500 grams). And that lens only achieves 1:5 magnification, where these Tamron lenses' USP is their 1:2 macro ability.

That makes 3 arguments for the Tamron f2.8 primes.

1. 1:2 max. magnification ability
   
2. comparatively low price
   
3. quite a bit more compact and light than the standard zoom alternative
   

One of my favourite images I have taken on APS-C was with 35mm at 1:2, so I can see the interest of these lenses for the niche audience that likes wider angles close ups upto 1:2. And of course, they do also do infinity stuff, besides the 1:2 ability.

Taken with a 35mm at 1:2, vertical images stitched., shot with Canon APS-C.
The FF equivalent to 35mm on Canon APS-C is 56mm. 

Also shooting with a 55mm 1:2 (max. magnification) lens on FF I can appreciate these Tamron 1:2 APS-C offerings.... The choice of FOV matters for the outcome, also at close up and macro ranges.


Taken on FF with a Nikkor 55mm f3.5 micro.
So if my platform would be Sony APS-C, I would be quite interested in this Tamron trio, due to their close up ability.

Very beautiful shots, BC. Thanks for sharing.

[Brightcolours]

Thanks JoJu. I have posted them before I am sure, but they illustrate well why these wider angle 1:2 magnification primes are not so uninteresting to others. Of course, these two were done with 35mm APS-C equivalents... But in one image I used that 35mm to create a wider view.

Another APS-C 35mm 1:2 mag. image:

The 35mm APS-C perspective gives a nice depth with not very distant flowers getting appreciatively smaller.

That effect of course gets more pronounced with 24mm APS-C

but the Tamron primes (of course) will show less astigmatism and CA issues.

[Rover]

Great shots there BC.

I can also see the merit of using these lenses as stopgaps:
- the 24mm is a bargain bin wide companion for anyone using the 28-75 as their main lens;
- ditto the 20mm, but it's also useful in the same role for anyone whose standard zoom bottoms out at 24mm;
- the 35mm is a bargain bin semi-standard companion for the users of the 17-28 or a wideangle that tops out at 24mm, before the tele.

It's really similar to how people are using a 50mm ish lens as a stopgap between the 16-35 and 70-something. I've been doing that for ages now.

Of course it would not be a consideration for someone who owns both the 17-28 and the 28-75.

[Brightcolours]

Valid points, Rover. For myself, I wanted a 20mm on FF to get really wide close up ability and bought a Voigtlander 20mm f3.5 partly for that. Regrettably, the Voigtlander is totally not suited for that (due to heavy astigmatism close up). If the 20/24mm Tamrons would have existed for EF mount, I would have bought one of those instead.