Sigma has unveiled a striking new full-frame mirrorless camera, the Sigma BF. It’s designed to be a small, simple-to-use camera for everyday photography, with a rethought user interface that aims to do away with film-era concepts and over-complicated menus. And in typical Sigma fashion, it’s distinctly unusually styled. I was lucky enough to be invited to its launch event at the firm’s Tokyo headquarters, to try out the camera for myself.

　　To be honest, my first reaction on seeing the Sigma BF was “what on Earth is that, and how am I supposed to hold and use it?”. Externally, the camera has a very simple design. From the front, it looks like a plain rectangle, with a textured fingergrip on one side of the lens mount. There’s just the shutter button on top, a single strap loop on one side, and USB-C port on the other. All the controls are on the back, and they’re very simple – buttons and a single dial, all placed under the control of your right thumb. It’s quite unlike anything I’ve seen before.

　　In your hand, though, the camera feels great, and comes across as a seriously premium product. This is thanks to its one-piece aluminium body, which is beautifully finished and feels extremely sturdy. Look closer and there are lots of neat little design touches too, including rounded corners at the bottom on the front left and back right, so they won’t dig into your hand.

　　Size-wise, the Sigma BF is small but not tiny, measuring 130.1 x 72.8 x 36.8mm and weighing 446g. That’s similar to other compact full-frame models such as the Sony A7C II and Panasonic S9, in terms of frontal dimensions. But it’s rather slimmer and lighter.

　　As Sigma promised, the user interface is entirely refreshed, and indeed rather unusual. For example, the camera does away with the concept of conventional PASM modes – instead you simply tell it which of shutter speed, aperture, ISO and exposure compensation you want to take control of, and which you’ll leave on Auto. Then to select and change a setting, you use the combined d-pad/rear dial. To my mind, this makes perfect sense. Elsewhere, the menus are strikingly simple and straightforward, with just a couple of screens full of settings.

　　Four things you need to know about the Sigma BF Unibody The BF’s body is crafted from a single solid block of aluminium for maximum rigidity. It comes in silver or black. Screen Viewing is solely via the fixed rear 3.2in touchscreen, with no viewfinder. A small status screen shows whatever setting you’re changing Grip The camera feels surprisingly secure in your hand, thanks to a small thumbhook and textured finger grip Storage There’s no memory card slot at all; instead, the camera comes with 230GB of built-in storage A photographer’s camera Features-wise, the BF is relatively uncomplicated, too. It employs a 24MP full-frame sensor, which offers a standard sensitivity range of ISO 100-102,400. Extended settings down to ISO 6 are also available, essentially by adding together multiple ISO 100 exposures. Continuous shooting maxes out at 7fps, which is fairly pedestrian by today’s standards.

　　Autofocus is a real step up over previous Sigma cameras, though, thanks to the addition of on-sensor phase detection. The BF also gains a limited level of subject recognition, covering humans and animals.

　　While Sigma is clear that it sees the BF as primarily being for photography, it has a reasonable video spec too. It can record in 6K or 4K at up to 30fps, or Full HD at up to 120fps. But you don’t get microphone or headphone sockets, or an HDMI output port. In this respect, the older Sigma fp remains a better option.

　　First impressions There’s no doubt that the Sigma BF is an incredibly striking camera, and it’s beautifully made too. I found the new user interface to be mostly straightforward, but then in some respects, frustratingly unintuitive to use. For example, it was far from obvious how to switch between still and video shooting. But this may just have been my jetlag-addled brain.

　　This is, clearly, a camera that will work best with small prime lenses, and in particular Sigma’s i-series primes with their metal barrels and built-in aperture rings. Indeed Sigma didn’t have any other lenses available to try with the camera at its launch event. The L-mount versions of these lenses will also now all be available in silver, to match the silver BF body.

　　It’s difficult to draw any definite conclusion about how well the BF works, and fits Sigma’s design goal of being a creative everyday camera, without spending more time shooting with it and trying out its new interface for real. But in a world where new cameras tend to be identikit SLR-shaped black boxes with complex controls and incomprehensible menus, it’s certainly a breath of fresh air. I’m really glad that Sigma had the courage to try something that bit different.