Lens Yongnuo YN-85mm F1.8S DF DSM — 85mm focal length, f/1.8 aperture, autofocus, full-frame compatible

The Yongnuo YN-85mm F1.8S DF DSM is a medium-telephoto prime lens designed for portrait, event and low-light photography. With an 85mm focal length and a bright f/1.8 maximum aperture, the lens produces a natural perspective for head-and-shoulders shots and smooth background separation. Built with an autofocus DSM drive and optics optimized for full-frame camera mounts, this lens is suitable for studio sessions and outdoor shoots where subject isolation and low-light performance are required.

Advantages

The fast f/1.8 aperture enables shallow depth of field and improved performance in low-light conditions while keeping lens size and weight moderate. Autofocus with a DSM (digital stepping motor) offers quiet, precise focusing suitable for both stills and video. Optical design and coatings reduce aberrations and flare for clear portraits and accurate color rendering. Full-frame compatibility preserves intended field of view and image quality on compatible cameras.

Suitable for

• Portrait photography — headshots, environmental portraits, family portraits
• Event photography — weddings, receptions, ceremonies
• Low-light situations — indoor and evening photography
• Video portraits and interview work requiring quiet autofocus
• Studio and outdoor portrait sessions

Key specifications

• Focal length: 85 mm (medium-telephoto)
• Maximum aperture: f/1.8 for shallow depth of field
• Autofocus: DSM (digital stepping motor) for quiet, precise focusing
• Compatible format: full-frame camera mounts (preserves intended field of view)
• Primary use: prime lens optimized for portrait and low-light photography

How to use

Mount the lens on a compatible full-frame camera body and set the camera to single-point or face-detection autofocus for reliable subject locking. Use the wide f/1.8 aperture to create a shallow depth of field and soften backgrounds; stop down as needed for greater depth of field in group shots. For low-light scenes, combine the wide aperture with appropriate ISO and shutter speed settings to maintain exposure while avoiding camera shake. When recording video, use the DSM autofocus mode for quieter focusing and smooth transitions.

Usage recommendations

Use focal-length framing at moderate working distance for flattering portrait perspective; for three-quarter or full-length portraits, increase subject distance and stop down slightly to keep the subject in focus. Keep lens front element and contacts clean, and store with lens caps when not in use to protect optical surfaces and maintain reliable autofocus performance.