By f/5.6 I'd say the corners get to good. Given that the DOF markings on the lens would suggest that 2 feet to infinity would be in acceptable focus at that point, it's quite possible to get edge to edge results that look very good with this lens. I'd say that the lens is best at f/5.6 whether you're using it in close or with subjects at far distances, so there doesn't seem to be any optical favoring with distance that we see in some lens designs. Une projection rectilinéaire classique comme avec un profil de correction Lightroom supprimera environ 30% de l’image et déformera les sujets près des bords. Le plugin Hemi lui conserve la plupart des pixels This is only the second fisheye lens being reviewed here, so it might make sense to have a short look what differentiates a fisheye lens from a normal ultra wide angle lens. Most of this section is taken from my TTArtisan 11mm 2.8 Fisheye review. The situation is not as bad as it is with many other M-mount ultra wide angle lenses (see this article for further reference) though, so it can still be an option if you are looking for a most compact fisheye lens or you only intend to shoot stopped down or at closer distances. Open full-size image in new tab. Same image at f/2.8 with 200% zoomed-in crop boxes showing star performance. Significant coma and loss of sharpness in corners. Some chromatic abberation. Open full-size image in new tab. 2 min. single exposure at f/3.5, ISO 1600, Canon EOS Ra, Bortle 3 sky.

The lens comes with an external 11mm metal viewfinder (very helpful if you don’t have live view, no frame lines in the viewfinder): So, from a strong central region, even wide open, we get to what I'd call a fair far corner wide open. That's actually a positive statement for a lens this wide. I've seen fisheyes that tend to not just go a bit blurry, but go all smeary as well. This one goes from acuity to slight blur wide open as you move from center to corner. There does seem to be axis-dependance to the blur, so I'd say there's likely astigmatism involved out in the corners. I don't see a lot of coma. The TTArtisan 11mm f/2.8 Fisheye is a manual focus lens that delivers 180° across the diagonal of the frame, what is sometimes called a "full frame fisheye." Full frame in that instance means that the fisheye produces image data all the way into the corners of the frame, and not a circular image as traditional fisheyes do.

This is a rather odd/interesting Fisheye zoom lens. At 8mm you have a 180° circular fisheye while at 15mm you have a 180° diagonal fisheye. If you have use for both this lens can be a good option. Not long ago Nikon introduced a similar lens, but as it is harder to adapt to Sony I recommend the Canon lens. The wide-angle design is also complemented by a bright f/2.8 maximum aperture, to suit working in available lighting conditions. The lens cap on this lens is the usual slip on cover. The rubberized felt inside ring that provides resistance so it doesn't slip off seems to do its job, though I wonder how well it will hold up over time.

Open full-size image in new tab. Same image at f/4 with 200% zoomed-in crop boxes showing star performance. Corner stars a bit sharper than at f/3.5. Still some chromatic abberation and coma, but not obtrusive. Open full-size image in new tab. 4 min. single exposure at f/4.5, ISO 1600, Canon EOS Ra, Bortle 3 sky. At 440g the TTArtisan lens is much lighter and also smaller. It looses when it comes to flare resistance and CA correction, but performs similar in terms of sharpness and coma correction. If you are looking for a similar fish-eye lens for a DSLR camera, I can recommend the older Rokinon manual 12mm f/2.8 ED, through at double the price. If you don’t want an object to distort like a magnifying glass held at arm’s length, keep that object in the middle, and small in the frame. Objects around it will bend, but the subject will remain largely planar. If you must, you can correct much of the fisheye business in post.

Images of the TTArtisan 11mm F2.8 Fisheye

As do all lenses of its type, the TTArtisan exhibited darkening of the corners, or vignetting, in this case by about 1.3 stops at the extreme corners at f/2.8, and just less than one stop at f/4. This was easily correctable in raw image processing to make the sky look uniformly illuminated. At 15.4 ounces (436g), the lens isn't light, but it's also not exactly what I'd call heavy, either. The smallish size and metal construction mean that it feels a bit "dense" in the hand. With our usual approach we cannot get decent values on the vignetting of fish-eye lenses. What I can tell you is that the vignetting figures are significantly lower than those of rectilinear ultra wide angle lenses, especially compact ones. Sony A7rII | AstrHori 12mm 2.8 Fisheye | f/2.8