Body cap lenses aren’t new – we have an Olympus Body Cap fisheye lens that performs beyond all reasonable expectations. The Funleader offers an angle of view almost as wide, at 18mm, but captures a corrected rectilinear (non-fisheye) image. It really is barely thicker than a body cap, though its aluminium construction means it is somewhat heavier.
But does it offer a serious alternative to a regular ultra-wide lens? Probably not. The Funleader is more of a quirky novelty than a serious lens. It will give you an interesting ‘look’, but it won’t match the features, flexibility or performance of a regular lens.
Focal length: 18mm
Mounts: Sony E-Mount, Canon RF-Mount, Fujifilm X-Mount, Nikon Z-Mount, Leica L-Mount
Field of view: 100°
Closest focusing distance: 0.8m
Lens construction: 6 elements in 5 groups
Body material: Aluminium
Weight: Approx. 80g
One key feature of the Funleader Cap Lens is that it’s just 15mm thick. Another is that it weighs only 80g. The real key features, however, are that this is a lens with a fixed f/8 aperture and fixed focus. Funleader says the focus range is 0.8m to infinity, which seems pretty optimistic for a full frame camera even with such a short focal length, but it does make this lens simple to use. You do really just point and shoot because there’s nothing to adjust.
The lens construction is 6 elements in 5 groups, which is perhaps a little more complex than we might expect in a novelty lens, and that’s married up with an aluminium construction and multi-coated lenses.
Build and handling
This is quite a dense and heavy little lens that feels well made. It locked on to our Sony body with a firm, solid click and with no play or looseness once in place. There are no moving parts, so there’s really not much else to say about the handling!
The only thing is, there’s no front or rear cover for the lens. It does come with a soft case, but when it’s mounted on the camera, there’s nothing to protect the front element when it’s in your bag.
There’s no aperture control, or any physical or electronic connection between the lens and the camera body, but you can sill use the camera in manual mode, aperture-priority or even program AE mode. The camera can simply measure the light coming through the lens and set the shutter speed accordingly.
There’s nothing to say about the autofocus performance because there is no autofocus, so it all comes down to the image quality.
This falls way short of what you would expect from a regular lens, with strong vignetting from uneven illumination into the corners of the frame, and the detail rendition is soft.
It’s not disastrous, though. A few moment’s work on our RAW files with Capture One’s Light Fall off adjustment, sharpening and structure tools revealed quite good images – you could make the same adjustments in other programs.
Or you can embrace the Funleaders’ soft and dreamy, heavily-vignetted look for what it is. As lo-fi looks go, this one is quite pleasant.
You have keep in mind the Funleader Cap Lens’s price and simplicity. This is an ‘alternative’ lens that’s not going to challenge the image quality of a regular lens, but instead offers a different lo-fi rendition. When you first take it out of its box, its weight and finish might raise your expectations a little, but your first batch of images will quickly dispel any illusions.
The Funleader Cap Lens is actually quite appealing, but more for artists and experimenters and certainly not for technical perfectionists. Is it worth the price? It's pushing the top end of what it's worth optically, that's for sure.
Currently the Funleader Cap lens costs $149/£109 and is available only from the Funleader Shop. We'll add other resellers when it becomes more widely available.