Last week, I received my brand-new Arsat-H 20/2.8 in Nikon mount. First, I shot quite a few test images with an adapter on Canon 5DmkII. A few days after, I went out and used it on the street. Let’s see how it performs.

Build

This lens is quite diminutive, about the size and weight of a Nikkor 50/1.4. It’s made in the Ukraine by Kiev Arsenal factory. According to the serial number, my sample was manufactured in 2002.

After handling and using the lens for some time, I find its build quality barely adequate. My copy is brand new, it was sealed in a box; yet its aperture already forms a very irregular shape, and its focusing ring is far from being even or reasonably smooth. The front of the lens barrel slightly wobbles. I haven’t seen many lenses built worse than this. However, it can still be mounted and used on the camera, and that’s what really matters. (Hope it lasts enough time for me to use).

Optical Construction

According to the manual, its optical construction includes a floating element, allowing it to maintain its optical quality across the focusing range.

[Arsat-H 20mm f/2.8 Optical Diagram will follow - I'll need to take a shot of the user manual]

Contrast, Flare and Chromatic Aberrations

It’s a great lens when it comes to shooting in contra light; flare is nearly non-existent. I was unable to produce any purple fringing, which is nice. Chromatic aberrations are pronounced. I guess it’s hard to correct in a UWA lens without aspherical elements. The CA are correctable in RAW workflow. The lens exhibits great contrast; kudos to Arsenal for getting the coatings and blackening right.

f/11

Flare is mostly under control; maybe not absolutely the best performance in this department, but more than acceptable. Minute ghosting when shooting into the sun.

f/11

Vignetting

Vignetting is stonger than I would like on a wide-angle lens though. Vignetting is very pronounced at f/2.8, almost but not completely gone by f/8, and still slightly visible (but correctable in the post) at f/11.

Sharpness and Colors

Optically, it’s nothing to rave about wide open. Center sharpness is reasonable, but edges and corners are very soft, exhibiting wide halos. At f/4, corners remain soft. However, by f/5.6 the lens improves, becoming rather sharp in the center and reasonable in the corners. At f/8, it’s sharp across the frame except extreme corners, which never reach even the ‘good’ territory. By f/11, diffraction starts to show, decreasing resolution slightly; the corners are sharper still. F/16 is soft due to diffraction. I mostly used this lens at f/11 for maximum sharpness across the frame; in lower light, f/8 and even f/5.6 can be used. Wider apertures are unusable to me.

f/11

Colors seem to be nicely saturated. The color balance is on a neutral side. Quite a nice performance here.

f/11

Distortion

Geometric distortion is noticeable, and is of a complex type. Barrel distortion in the middle of the frame turns into pincushion distortion near the edges. This lens is hardly suitable for architectural photography.

Verdict

Used between f/5.6-11, this lens can produce reasonably sharp images. Being a 20mm full-frame rectlinear ultra wide angle lens, this one competes with some much more expensive lenses as well as used UWA’s such as Tamron and Tokina 17/3.5. If you’re going to use an UWA lens infrequently, this is a good, reasonably priced choice. I paid $113 for my copy; that’s about right for this lens. For $150, there are better alternatives, and $200 buys a really nice manual focus UWA lens. For serious wide angle fans, I guess this lens won’t cut it. To me, it’s fine.