Conclusion
Pros
- Inexpensive way to add an ultra-wide lens to your kit
- Well constructed
- Good central sharpness and acceptable edges at smaller apertures
- Pleasing bokeh
- Excellent flare control
- Good color and contrast
Cons
- Edge sharpness is poor wide open
- Heavy barrel distortion without digital correction
- Some purple fringing possible at wide apertures
- Bayonet mount seems like it may not hold up over years of use
- Can’t use filters
I have to say, I didn’t really hold out very high hopes for the Sony 21mm Ultra-Wide Conversion lens. These sorts of lenses are often sub-par optically, but I’m glad to say that this lens is actually pretty good. While shooters who use ultra-wide-angle lenses often should probably look to the Zeiss FE 16-35mm f/4, the FE 21mm conversion lens allows you to get a nice ultra-wide lens for minimal additional cost. Overall sharpness is good, though not great, and the excellent flare control and solid color and contrast make this a very viable option for those seeking to go wider.
On the down side, there is heavy barrel distortion that effectively requires correction in post-processing, and the inability to use filters will limit some of its use as a landscape lens. If you really aren’t sure about buying the FE 28mm on its own, I’m not sure it’s worth it to purchase 28mm and this lens just for the 21mm capabilities. In many cases you may be better off saving up for the 16-35, or using a manual focus lens such as the Canon FD 20mm f/2.8, which should provide a bit better image quality.
However, for those who already own or are planning to buy the Sony FE 28mm f/2, I think the 21mm UWA conversion lens is almost a no-brainer add-on, unless you already have the FE 16-35mm. It’s inexpensive and definitely good enough to produce high-quality images.
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Image Samples
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Great review as always. I just bought this addon lens and can’t wait to review it myself. I wonder if in the long run the 16-35 would be the better option, however.
Thanks for the review. It strikes me that the cost of the adapter is about as much as a few of the old MF glass options around this (21mm adapted) focal length- eg canon Fd 19 or 20 or Olympus 21 etc. For landscape use on an A7II from what you have seen, (keeping in mind that shooting stop would be at least an 8) How does the IQ compare? I have been using an fd 24mm it is very sharp copy and was very economical. (My Fd 28 is not!) It has been hard to justify getting something else modern so far as i keep testing at the local camera store and nothing has been sharper or that much superior to justify cost. I really liked the Sony 28, but what I need is wider! Enter the adapter. what’s your take? Cheers!
I wonder if there is a way to use this with another lens.
Can you post the back of the lens?
are there moving parts in it?
thank you
I know this is an apple vs orange comparison, but which one will come up on top in terms of optics, IQ, sharpness etc? FE28 + 21mm adapter or Fuji XF14mm?
The Fuji by a mile. Not that the 21 isn’t a good combo, but the Fuji is an exceptional lens. Sharp to the very corners, no distortion, etc.
Any thoughts on how it compares to the ~19-21mm legacy primes at a similar price point? I’m thinking of the Nikon 20mm f/2.8 AI and D, Canon FD 20mm f2/.8, Minolta Rokkor-X 20mm f/2.8, Voigtlaender 20mm f/3.5, Olympus 21mm f/3.5, and Pentax 20mm f/4, all of which are ~$200-350. Probably some others I’m forgetting as well.
I had been planning on getting the UWA converter, based on my good experience with the SEL16F28 + VCL-ECU1 on the NEX. The SEL16F28 wasn’t a great lens, but the VCL-ECU1 did a great job, was cheap ($100), and seemed to increase IQ rather than degrade it.
Then I realized that the Nikon 20mm f/2.8 that a friend was selling weighed the same as the UWA converter. If it can perform any better than the FE 21mm, it might make more sense for me.
Thanks for a great review, as usual.
thank you for your great review … i just ordert the combo to have a closer look.
best regards
jan