Fisheye lenses extend the creative options available in infrared photography. The Rokinon 8mm f/2.8 UMC Fisheye II is an APS-C lens available for Canon EF-M, Fujifilm X, Samsung NX, and Sony E mounts. This lens is compact and lightweight for a fisheye, which pairs well with small APS-C mirrorless cameras.
The Rokinon 8mm is a manual focus lens. Due to the vast depth of field, focus to infinity unless shooting at extremely close distances. Enable focus peaking in your camera to validate focus.
The front element of this lens features a convex design. There are no filter threads for circular filters. Since you cannot use external filters, this lens is best suited for cameras converted to a specific filter, such as 590 or 720 nm, instead of full-spectrum conversions. It could also work well with clip-in filters placed in the flange between the lens and camera, but I have yet to test this.
There are no electronic contacts. Images will not contain EXIF data. I tend to shoot with a consistent f-stop, such as f/4 or f/5.6, and update the metadata after shooting.
Infrared Hot Spots
From f/2.8 to f/5.6, hots spots are barely perceptible. At f/8 and higher f-numbers, a small hot spot with a faint halo is visible. Since fisheye lenses have more depth of field than normal lenses, you have plenty of depth, even at lower f-numbers.
Infrared images shot on a 590nm-converted Fujifilm X-T20 with the Rokinon 8mm f/2.8 UMC Fisheye II.
Visible Light Images
Visible light images shot on a Fujifilm X-T2 (unconverted) with the Rokinon 8mm f/2.8 UMC Fisheye II.