The Sigma 50-100mm F1.8 DC HSM (A) lens for Canon is a premium mid-telephoto zoom lens designed specifically for APS-C format DSLRs. Here’s a detailed overview of its features and specifications:

Key Features

Focal Length: The lens offers a focal length range of 50-100mm, which translates to an equivalent of 80-160mm on APS-C cameras, making it ideal for portrait and event photography.

Aperture: It boasts a constant maximum aperture of f/1.8 throughout the zoom range, allowing for excellent low-light performance and greater control over depth of field for creative effects.

Optical Design: The lens incorporates advanced optical elements, including:

Three F Low Dispersion (FLD) elements and one Special Low Dispersion (SLD) element, which significantly reduce chromatic aberrations and color fringing.

A high-refractive index glass element that enhances clarity and sharpness across the focal range.

A Super Multi-Layer Coating that minimizes flare and ghosting, ensuring high contrast and color fidelity even in challenging lighting conditions.

Autofocus System: Equipped with a Hyper Sonic Motor (HSM), the lens delivers fast and quiet autofocus, with full-time manual focus override available at any time for precise control.

Construction: The lens features a robust build using Thermally Stable Composite (TSC) material combined with traditional metals, ensuring durability across varying temperatures. The brass bayonet mount adds to its longevity.

Diaphragm: It has a rounded nine-blade diaphragm that contributes to smooth bokeh, enhancing the aesthetic quality of out-of-focus areas in images.

Tripod Collar: A fixed rotating tripod collar is included for improved stability during prolonged shooting sessions, with 90° click stops for easy orientation adjustments