A brief update on the Rokinon 12mm lens that I previously reviewed. I did get another copy of the lens and color cast that I saw in the previous lens was gone. So that is great news. I have shot with the lens some more including getting out and shooting under the stars. One of the main reasons I was interested in this lens was it might make a good lens for nightscapes. I have to say that it really does make for a good lens for night shots. The lens is still a bit soft at f2, but that is to be expected with a lens that is this wide. It is not to say that it is unusable, but it does perform better stopped down. If there is nothing close to the lens and most items are at infinity focus then it is hard to see the softness. For most instances this not a problem and it is a wonderfully fast lens. I found that stopping down to f2.4 or f2.8 resulted in a general improvement, and by f4 is pretty good all over. That being said for quick nightscapes the faster aspects can be beneficial, and it will show less trailing. Even though this is a wide lens, with the crop factor it does give the field of view of an 18mm lens so that means that stars will start to show trailing before 30seconds, depending on where you point the camera.
This shot was from a quick trip out to Joshua Tree National Park, taken with a Fuji X-T1 and the Rokinon 12mm at f2.0 and ISO 3200, single exposure of 30 seconds.
The lens is a good deal considering the price and the performance. The downsides are the full manual focus and aperture and the lack of details being recorded in the EXIF of the camera. The Fuji does allow the setting the focal length so that is recorded, however the aperture used is not recorded. The lens hood also leaves something to be desired. It is really loose fitting and will sort of snap into place but there is a lot of play and I have found that it has come off sometimes in the camera bag, poor design, in my opinion. It is a functional hood for the wide angle lens but it could be better. The positives pretty outweigh the negatives. There is little chromatic aberration and little coma in the corners. I do expect some in a lens this wide but it is very negligible. Color and contrast are quite good. It has well corrected optics, much better than one would assume with a lens of this price point. It is also compact and relatively small for a wide angle lens. Focus ring and aperture ring are smooth and have a good feel to them. The aperture ring is detented at half f-stops from f2-f22. The lens feels solid and well constructed and is not weather resistant. The front is threaded for 67mm filters, which is nice.
I would recommend this lens, especially for the price point. I would give the Fuji 14mm f2.8 lens the edge, it has the full autofocus, as well as manual focus and the ability to have auto aperture, but the Fuji is substantially more money. The Rokinon is a bargain and for me a nice lens to have in the bag and one that will get used, for nightscapes and landscapes. I will still keep my Fuji 14mm. The Fuji is a bit better corrected optically but the Rokinon does pretty well. The extra 2mm of the Rokinon does make a difference. I was also interested in the Rokinon 10mm but it is twice the weight of the 12mm and is not as appealing. The 12mm was designed for mirrorless cameras and therefore the size and weight are scaled accordingly, while the Rokinon 10mm appears to be a verison of their DSLR lens with a Fuji X-mount on the end, not as appealing. I am happy enough with this Rokinon that I do not feel the need to compare it to the Zeiss 12mm lens for Fuji. For ultra wide I will stick with the Fuji 10-24mm f4.