Sigma 20-200mm F3.5-6.3 DG Contemporary

The Sigma 20-200mm F3.5-6.3 DG Contemporary is a full-frame all-in-one zoom for Sony E and Leica L-Mount. Sigma calls it the first high-power zoom for full-frame mirrorless cameras that combines a 20mm wide end with a 10x zoom ratio. It targets travelers and everyday shooters who want ultra-wide to telephoto coverage in one lens, with the aperture falling from F3.5 at 20mm to F6.3 at 200mm.

Optical design

The design has 18 elements in 14 groups, including 1 FLD, 3 SLD and 4 aspherical elements. According to Sigma, high refractive index glass reduces lens group movement during zooming, which keeps the internal structure simple and the body slim. The diaphragm has 9 rounded blades, and the smallest aperture is F22 at the wide end and F40 at the long end. Maximum magnification is 1:2 between 28mm and 85mm. Minimum focus distance is 25cm at 20mm and 65cm at 200mm, with 16.5cm quoted at 28mm.

Autofocus and handling

An HLA (High-response Linear Actuator) drives the focus. The lens has a focus mode switch and a zoom lock switch that holds it at the wide end so the barrel does not extend under its own weight. The lock also releases when the zoom ring is turned. Sigma's specification lists no optical stabilizer, so stabilization has to come from the camera.

Build and size

The L-Mount version weighs 550g and is 115.5mm long, the Sony E version 540g and 117.5mm, both with a 77.2mm diameter and a 72mm filter thread. Sigma points out that the zoom ring is only 70.4mm in diameter. The construction is dust and splash resistant and the front element has a water and oil repellent coating.

Where it fits

There is no direct predecessor, as Sigma presents it as the first lens of its kind. In the Sony E system, the Tamron 28-200mm F2.8-5.6 Di III RXD, the Tamron 28-300mm F4-7.1 Di III VC VXD and the Sony FE 24-240mm F3.5-6.3 OSS are the nearest all-in-one alternatives, though none starts at 20mm. The Sony FE 20-70mm F4 G does, but ends far earlier. For L-Mount, the Panasonic Lumix S 28-200mm F4-7.1 Macro OIS is a comparable superzoom with built-in stabilization.

Pros and cons

Pros

• 20mm wide end with a 10x range in one full-frame lens
• Maximum magnification of 1:2 between 28mm and 85mm
• 540 to 550g, compact for its range
• Dust and splash resistant, with zoom lock

Cons

• Variable aperture closing to F6.3 at 200mm
• No built-in optical stabilization
• Not suited to shallow depth of field or very dim light

Verdict

The Sigma 20-200mm F3.5-6.3 DG Contemporary is a travel zoom for photographers who prefer one lens over a bag of primes and accept the modest aperture at the long end. Its 20mm start sets it apart from most superzooms on full frame.