Sigma 4 5mm F2 8 EX DC HSM Circular Fisheye Review | 54 Data compared

The Sigma 4.5mm f/2.8 EX DC HSM is a unique circular fisheye lens specifically engineered for APS-C cropped sensor cameras, providing them with a complete 180-degree field of view within a single frame. In real-world testing across Asia, the reviewer noted that the lens integrates comfortably into a standard camera kit, operating smoothly with an fast f/2.8 maximum aperture and a Hyper Sonic Motor (HSM) for focusing. Its extreme minimum focusing distance of just 0.75 inches (19mm) allows photographers to get exceptionally close to subjects, making it an excellent creative tool for capturing exaggerated perspectives, architectural curves, converging lines, and astrophotography. However, the lens presents specific usability and design challenges. Its primary downside is a protruding front glass element that leaves it vulnerable to scratches, causing the reviewer constant worry and necessitating strict use of the lens hood and cap. The extreme 180-degree field of view also requires a steep learning curve; users must carefully check the edges of the frame to avoid accidentally including their own feet or hands in the shot. Additionally, standard front-mounted filters cannot be used...

Summary of Pros and Cons Pros: Outstanding frame-centre image resolution, robust premium EX build quality, excellent ghosting and flare suppression against bright light, and a generous accessory package backed by a reliable manufacturer warranty. Cons: Significantly weaker optical resolution at the extreme frame edges, a slightly narrow manual focusing ring, and a redundant autofocus mechanism due to the lens's inherently massive native depth of field.

The Sigma 4.5mm f/2.8 EX DC HSM Circular Fisheye for Nikon F-DX is an ultra-wide prime lens designed to project a full 180-degree circular image onto APS-C sensors, featuring a fast f/2.8 aperture and rapid, quiet autofocus via the HSM motor. Its key strengths include an extremely close 13.5 cm minimum focusing distance and a durable build, making it ideal for unique, immersive, and exaggerated perspectives. Conversely, the specialized design imposes limitations, such as the lack of image stabilization and the inability to use standard screw-in front filters due to the convex element, which instead requires rear-mounted gelatin filters. Users must also note the absence of an aperture ring, requiring electronic control, and the potential for fingers to intrude into the wide 180-degree field of view.

The Sigma 4.5mm F2.8 EX DC Circular Fisheye HSM is a specialist lens designed for APS-C sensor digital cameras, offering a unique 180-degree circular view of the world. Weighing 470g with a diameter of 76.2mm, it features an excellent, high-quality finish and quick, reliable autofocusing operation. Its standout pros include a remarkable close-focusing ability down to 13.5cm (providing a 1:6 magnification ratio) and impressive peak sharpness when shooting at apertures between f5.6 and f11, with f8 being the sharpest setting. On the downside, the lens suffers from noticeable softness at its extreme aperture ranges of f2.8 and f22, alongside inevitable optical aberrations and a drop-off in sharpness right at the outer edges of the circular image. Managing exposure presents a significant challenge due to the massive field of view, often requiring exposure bracketing or HDR techniques to resolve. Furthermore, users must look out for a confusing two-part lens cap design that can accidentally obstruct shots, and the extreme 180-degree perspective makes it incredibly easy to accidentally include your own feet or body in the frame.

Overview and Pros The Sigma 4.5mm f/2.8 EX DC HSM is a unique, solid metal-mount circular fisheye lens designed specifically for APS-C sensors. It provides an extreme 180-degree field of view that projects a sharp, circular image surrounded by black space. Reviewer Sybren A. Stüvel highlights its excellent center sharpness, fast and silent ultrasonic autofocus motor, and bright f/2.8 maximum aperture, which aids in low-light shooting and background blurring. The lens's incredibly close minimum focus distance of 13.5cm and massive coverage make it highly fun and efficient for shooting 360-degree panoramas—requiring only six overlapping shots for full coverage—and recording edgy, wide-angle videos. Cons and Final Verdict Despite its high utility, the lens suffers from notable flaws, including severe chromatic aberration and purple fringing in high-contrast areas near the outer edges of the circular frame. Structurally, the focus ring is awkwardly placed too far forward, making it easy for the photographer’s fingers to accidentally slip into the 180-degree frame. Additionally, the aperture mechanism is surprisingly loud, and the rear gelatine filter holder is of limited use since it cannot rotate for...