Sigma BF: two-minute review
I knew that the Sigma BF would frustrate me at times, but what I wasn't prepared for was how much I would enjoy making pictures with the camera.
This unique and boldly minimalist camera, which has been likened to Apple's products, oozes character, and despite its many design and performance concessions I've come to love it.
Yes, the 24.6MP full-frame Sigma BF's minimalist design polarizes opinion – for some it's an object of desire, for others it's a firm no. However, even hardened fans of the camera, who now include me, will admit there's maybe one concession too many.
Rated using a conventional scoring system, the Sigma BF comes up short because its limitations are many. It doesn't have a viewfinder; its touchscreen is fixed; memory is internal only (a 230GB SSD and no card slot); the 24MP full-frame sensor isn't stabilized; its ergonomics could be better; battery life is modest; and key connections ports for video, such as mic in and a headphone jack, are absent.
That said, cameras can't be reviewed purely by ticking boxes. They're creative tools, and if you find one that gets you, and brings out the creator in you, then what it scores in a review is less relevant.
A similarly-priced, conventional mirrorless camera like the Nikon Z6 III gives you all the tools you need, wrapped in a sensible design with superb ergonomics, and it 'scores' better. However, if you want a bit of excitement, and a stunning and unique camera that can delight, frustrate, then delight again from one beat to the next, the BF is the ticket.
For seasoned photographers, there’s a re-learning process with the Sigma BF in terms of navigating its nondescript controls and minimalist menus. You need to spend some time getting to know the BF. Familiarize yourself with its quirks and its joys, and most other cameras feel somehow dull and characterless by comparison.
It's also a sensational pairing with Sigma's Contemporary I-series lenses – I had a new silver version of the 35mm F2 DG lens to match the silver BF. Sigma, if you're reading this: producing a pancake lens next, that pairs with the BF's compact body, should be a top priority.
Sigma says the BF stands for 'Beautiful Foolishness', I've read other reviewers liken it to a 'Best Friend'. For me, it’s Brilliantly Flawed and I'm a Big Fan.
Whatever its technical compromises, the Sigma BF is a design masterstroke. It's a beautifully imperfect thing that deserves its place in your hand. Relationship status? Seeing someone.
Sigma BF: price and release date
- The Sigma BF body-only costs $1,999 / £1,969 / AU$3,995
- It's available for pre-order in silver or black versions
- Sigma has also launched silver versions of multiple I-series lenses
Sigma lenses are typically around half the price of proprietary brand equivalents, but what of the brand's cameras? Well, the BF costs $1,999 / £1,969 / AU$3,995 body-only, which on the one hand is pretty steep for a 24MP full-frame camera with no viewfinder.
However, this is no ordinary camera. When you consider the BF's build quality – the chassis is machined from a single ingot of aluminum, and the camera has premium touch-sensitive controls – then suddenly it feels more reasonable.
Pre-orders are open now, and the BF is available in silver or black versions – interest in the silver version has been particularly high. However, reportedly Sigma can only make nine Sigma BF units per day, and so the lead times for orders could dwarf even those for 2024's most sought-after camera, the Fujifilm X100VI.
- Price score: 4/5
Sigma BF: specs
Sigma BF: design and handling
- Chassis machined from a single ingot of aluminum
- Nondescript controls, some of which are touch-sensitive, plus simple menus
- Internal SSD memory only, no card slot
- No mic or headphone port, just a USB-C port
A camera that's machined from a single ingot of aluminum in a process that takes seven hours, with production limited to nine units per day, should be special. The BF is just that.
It's true that the Sigma BF's minimalist design won't be for everyone. It's distinctly Apple-like in terms of its design, at a time when retro cameras like the Fujifilm X100VI are trending. Personally, I've found the BF to be one of the most fascinating cameras in recent memory.
Its premium quality is obvious, right down to the smallest details – even the the metal body cap, which I dedicated an entire article to. The camera is weather-proof and feels rock-solid – I'd fear more for any surface it came into contact with, even though of course I wouldn't want to thrash such a lovely camera around.
With its clean lines and stripped-back control layout come various design concessions, particularly if you've been spoilt by other mirrorless cameras that place plentiful controls at your fingertips.
There's no grip to speak of, just a textured front half; a design choice that feels more aesthetic than anything else, and which complements the matte finish beautifully.
As such, the BF is best used with small lenses, especially Sigma's I-series of Contemporary primes. Sigma was on the ball in launching silver versions of some I-series lenses to match the new silver BF – I had the new silver 35mm F2 DG for this review.
These I-series lenses are pretty small, none more so than the 45mm F2.8. That said, there's no true pancake lens for Sigma's L-mount, and I'd like to see one to full complement the BF's ergonomics.
Each button and control is beautifully dampened, and – get this – two of the buttons are touch-sensitive: the menu button and the playback button. If you half-press the playback button, your latest image pops up on screen until you let go. Fully press the button in and you enter playback mode. Quality.
Markings on the buttons are suitably nondescript, so it'll take you a while to workout what each one does. Also, once you're in a menu, it's not all that obvious how to make exposure changes – a prize goes to whoever works out how to select or deselect the auto option in exposure settings the fastest.
Finding commonly used settings is no problem, though. There are three simple menus to navigate: the main one with your most-used settings, and two sub-menus. This simple setup feels very Hasselblad X2D 100C.
In that top menu, you can scroll through the options using the control wheel, with the latest setting being displayed on a charming, tiny LCD. Via this, quick changes to settings like color profiles are possible.
Arguably Sigma's most controversial design choice was to limit storage to an internal SSD only. That's fine, so long as the SSD is reliable – and we've no reason to believe it won't be – but if there's an issue with it the camera becomes useless without a costly repair (assuming that is indeed possible).
I love cameras that include built-in memory as a fail-safe, but that's when it's in addition to removable media such as an SD card. Internal memory only will be a dealbreaker for some people.
To upload photos from the BF you'll need to connect it via the USB-C port, which is also used to charge the camera. I found the upload process super straightforward, and speedy to a MacBook Pro.
The exterior is suitably stripped-back too, meaning there's no mic input, headphone jack, HDMI or even loops on both sides for a shoulder strap, just on one side for a wrist strap.
I don't mind all of the above. What I did miss the most is having a viewfinder or a tilt / vari-angle screen. In bright sunlight I naturally found myself bringing the camera up to my eye as if a viewfinder was there to compose the shot, while at awkward low angles I wished for a tilt screen.
Both or either of those display features would make the BF more practical, but I understand why they're absent – how could Sigma otherwise make such a beautifully minimalist camera?
- Design score: 4.5/5
Sigma BF: features and performance
- 8fps with continuous AF, recorded onto rapid internal SSD
- Below-average 260-shot battery life
- No IBIS, just electronic stabilization for video
If you want an all-singing all-dancing mirrorless camera, the Sigma BF is not for you. Sure, its startup time is rapid, but it lacks many of the powerful features that we've come to take for granted in cameras at this price point and above.
Take the 24.6MP sensor – it's not stabilized. That's not a dealbreaker for what will surely be an everyday camera for photographers, and used with fast-aperture prime lenses, but I'd love to see it – after all, in-body image stabilization is part of an internal component, and so including it wouldn't impact the BF's minimalist design.
For video, there's the option for electronic stabilization, which imposes a 1.25x crop to the image area, meaning it's not available for the 6K option.
The burst shooting with continuous AF drive mode maxes out at 8fps, so it's not the quickest. However, sequences can run for longer than you'll likely ever need: up to 350 raw images or 1,000 JPEGs. Buffering time for those sequences, before the camera is ready once more to perform fully, is shorter than on most rivals too.
As mentioned, there's no card slot, and images are saved to an internal 230GB SSD. You can upload photos via the multi-purpose USB-C 3.2 port, which is rated up to 10Gbps and can also be used for any one of the following functions at a time: external video output, charging and power delivery, cable release, external mic, and headphone output.
Sigma has created a new BP-81 battery for the BF – it's a tiny 3,300mAh unit that's rated for a meagre 260 shots, although I don't mind the lower-than-average shot life when you consider how compact the BF is.
Autofocus is a hybrid phase-detection and contrast-detection system, with subject tracking for humans and animals. It's proven pretty reliable overall during my testing, especially for close-up portraits, but I've certainly used more sophisticated systems from the likes of Sony, Canon and Nikon.
Part of the issue with autofocus is relying on a fixed touchscreen that's not always the easiest to see, depending on the shooting conditions. You hope focus is spot on, but it isn't always.
Another element that limits autofocus performance is that the focus options you have to choose from are relatively basic – this is a minimalist camera in just about every way. I'd also say, based on my experience of both cameras, that the Nikon Z6 III is much better at picking up subjects that only take up a small portion of the frame.
As for video, the BF features built-in stereo mics, but no dedicated mic input, just mic connection via the multi-purpose USB-C; and the stereo mics are particularly susceptible to wind distortion. In short, many of the features that video users rely on are absent – the BF is more a photographer's camera that happens to shoot lovely-quality 6K video.
- Features and performance score: 3.5/5
Sigma BF: image and video quality
- 24.6MP photos in detail-rich 14-bit raw universal DNG format
- 6K video from the full width of the sensor, no EIS available at this resolution
- 13 color profiles for photos, L-log for video
Despite its rather conventional-sounding 24MP full-frame sensor, the Sigma BF is capable of producing highly-detailed images with gorgeous color.
Special mention must go to the superb 35mm F2 DG lens I was testing the camera with – detail is pin-sharp from center to edges, with a lovely focus fall-off when you're shooting at the maximum f/2 aperture.
There are plenty of other superb L-mount lenses to pair with the BF, and Sigma lenses are reasonably priced too. That said, I do think that Sigma needs to prioritize producing a pancake lens that truly complements the BF's compact body, especially while sales for the camera are likely to be strong. A tiny 35mm f/2.8 should be doable.
The photos in the gallery directly below are a selection of the kind of everyday images that the Sigma BF is so adept at capturing.
As with Leica, I always appreciate that a Sigma camera's raw files are the universal DNG format, meaning that just about any editor happily accepts the files; and they're detail-rich 14-bit files, no less.
Shoot in raw and JPEG simultaneously, and the standard color settings and full image area is kept for raw files, but your active color mode is applied to JPEGs. There are 13 modes to choose from for photos, and there are a few crackers amongst them.
The Calm color profile is Sigma's version of natural / muted, while Rich is a vibrant profile. I'm a fan of the BF's natural '709 Look' for photos, even though it's based on the Rec.709 profile traditionally used for video, plus the punchy and trendy Teal and Orange. It's easy to scroll through these options quickly to make your selection.
Here's the entire list of color modes: Standard, Rich, Calm, Powder Blue, Warm Gold, Teal and Orange, FOV Classic Blue, FOV Classic Yellow, Forest Green, Sunset Red, Cinema, 709 Look and Monochrome.
Street photography is a forte of the Sigma BF, as you can see from the collection of images below.
Would I prefer the BF had a 61MP sensor, like the one in Sigma's own fp L? Sure. And a stabilized sensor too. Those extra pixels would give greater scope for cropping into images taken with a lens like the 35mm F2 I had for this test, for the times you can't get close enough, while in-body image stabilization makes handheld shooting easier in various conditions.
All the photos you can see below were taken with the BF's autofocus with subject tracking active, and the close-up portraits are reliably pin-sharp on the eyes. My hit ratio in low light was less reliable, but impressive nonetheless.
Video specs are decent, with 6K 30fps video in Sigma's L-log profile looking particularly lovely after grading, though you'll miss out on electronic stabilization in 6K, which rules out handheld footage on the move – the sample video below includes shaky unstabilized clips as I walk through London, plus a selection of the color profiles so you can appreciate the different styles.
However, it's the distinct lack of supporting features for video that plants the BF firmly in the photography camp, rather than it being a hybrid model.
- Image and video quality score: 4.5/5
Sigma BF: testing scorecard
Should I buy the Sigma BF?
Buy it if...
You love minimalist tech
I thought the Hasselblad X2D 100C was peak minimalism, but the Sigma BF is another level – there isn't even a memory card slot!
You want a camera that stands out from the crowd
The camera market is flooded with conventional DSLR-style mirrorless cameras; the Sigma BF couldn't be more different.
You want a small everyday camera
Considering its full-frame sensor, the BF is compact, and pairs nicely with Sigma's dinky Contemporary I-series lenses.
Don't buy it if...
You value function over form
Design is the BF's selling point... if you want something different. However, other cameras at this price point will offer more control and more features.
You shoot video a lot
The BF can record lovely-looking 6K video with Sigma's L-log color profile, but it lacks most supporting features needed for video, such as in-body image stabilization, and mic in and headphone out ports.
You need removable storage
The BF doesn't have a memory card slot, just an internal SSD, so if something goes wrong with the internal memory it's game over. We wouldn't expect any issues, but it's something to worry about.
Sigma BF: also consider
The BF follows two other Sigma full-frame cameras with similarly compact form; the fp (24MP) and the fp L (61MP). The fp L is more readily available and has the pricier, higher-resolution sensor yet costs the same as the BF, while the fp costs around 20% less, but is harder to find new. The BF wins for design, while the fp models arguably have better features and more conventional controls, even if the BF has improved in certain areas, such as autofocus performance. All three cameras use the same L-mount.
Read our in-depth Sigma FP review
Full-frame 24MP cameras at the BF's price point are plentiful. Most have a conventional design, such as the Canon EOS R6 Mark II and Nikon Z6 III. However, there are other cameras that pack a similar punch but whose design and user experience are key, such as the Nikon Zf. Unlike the modern, minimalist Sigma BF, the Nikon Zf is a retro model with exposure dials and faux leather finish.
Read our in-depth Nikon Zf
How I tested the Sigma BF
- Sigma loaned me the silver version of the BF for one week
- I tested it with the Sigma 35mm F2 DG Contemporary lens
- I mostly used it for everyday and street photography, taking between 500-1,000 photos and videos, and I also tested its video features
I tried to use the Sigma BF as much as possible during a oneweek loan period, taking it with me everywhere, including on city commutes and walks. As you can see from the photos, I had the silver BF, which was the version I was hoping for, together with a new silver version Sigma 35mm F2 DG Contemporary lens.
I've used the BF in bright sunlight and on cloudy days, as well as at night. I've made photos using the various color profiles and autofocus modes, as well as videos at the various resolutions.
First reviewed April 2025
