A Look Inside the Ultra-Minimalist and Beautiful Sigma BF

Kolari Vision has released a detailed disassembly and teardown of the Sigma BF, offering a rare look inside one of the most visually distinctive mirrorless cameras on the market.

Known for its infrared conversions, optical filters, and deep involvement in experimental imaging workflows, Kolari Vision approaches the teardown not just from a hardware curiosity standpoint, but with a focus on optical performance and system design. Kolari also highlights its products that are compatible with Sigma cameras, like its Magnetic Clip-in Filter system designed for cameras like the BF, fp, and fp L.

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But beyond filtration and workflow integration, the teardown itself reveals something more striking: a camera built around extreme minimalism and tightly integrated internal engineering.

As PetaPixel reported when the BF was announced early last year, the camera is milled from a single block of aluminum, and Sigma can make only about nine units per day. It takes seven hours to mill the block for a single camera.

A Design So Minimal It Hides Its Entry Points

Kolari Vision notes that the Sigma BF stands out immediately for its unusually clean exterior design. In fact, the camera is so stripped back visually that the teardown process begins with some detective work.

Unlike most mirrorless cameras, there are no obvious external screws or a traditional removable baseplate. Instead, the first access point is hidden beneath the rubberized bottom grip, which conceals the primary fasteners holding the body together.

From there, a layered structure begins to emerge, with a plastic cover above the internal assembly, serving as an initial barrier to the camera’s densely packed internals.

Layered Internal Construction and Tight Component Packaging

Once inside, Kolari’s teardown shows that the Sigma BF uses a highly layered internal layout. Multiple small printed circuit boards (PCBs), metal brackets, and ribbon cables must be carefully removed in sequence before reaching the main logic board.

The LCD screen is also removable, but requires controlled heat to soften the adhesive before it can be safely separated from the body. It connects via a single ribbon cable, underscoring the camera’s highly integrated internal design.

As disassembly continues, additional ribbon cables and structural screws reveal how tightly each component is packed into the camera’s aluminum frame. Kolari notes that even after removing several visible fasteners, further hidden attachment points prevent immediate access to the main board.

Hidden Screws and a Surprisingly Dense Assembly

One of the more notable discoveries during the teardown is the presence of a hidden screw beneath the camera’s scroll wheel, an occasional but always significant design choice in compact camera engineering.

This hidden fastener helps secure the internal framing that would otherwise appear inaccessible from the exterior. Once removed, additional internal plates and ribbon connections begin to free up larger assemblies within the body.

Kolari ultimately removes the main circuit board by carefully lifting it from the internal frame after disconnecting multiple ribbon cables and structural supports. The process reveals just how tightly integrated and space-efficient the internal layout is.

Sensor Access and Final Disassembly Stage

With the main board removed, attention shifts to the sensor assembly. At this stage, the teardown becomes more straightforward, with the remaining barrier primarily being the battery compartment structure and its associated mounting screws.

After removing these components, the sensor assembly is finally exposed. According to Kolari, only perimeter screws remain at this stage, making sensor extraction relatively simple compared to earlier steps in the teardown.

The battery compartment itself is also removed during this phase, revealing how it partially reinforces the structural rigidity of the camera’s internal architecture.

A Surprisingly Accessible Yet Densely Packed Camera

Despite its minimal exterior and tightly packed interior, Kolari Vision concludes that the Sigma BF is ultimately a straightforward camera to disassemble, once the correct entry points are discovered.

The key takeaway from the teardown is not complexity for its own sake, but rather how much functionality, structural support, and electronic integration Sigma has managed to fit into such a clean and minimal body design.

There are many more details and photos available on Kolari’s blog post about the Sigma BF teardown.

Image credits: Kolari Vision