Schneider-Kreuznach Blue Ring LS 240mm f/4.5 AF Leaf Shutter Lens for XF 645 Bayonet Mount, Black Review

The Schneider-Kreuznach Blue Ring LS 240mm f/4.5 is a medium telephoto lens designed for Phase One XF and other medium format cameras with the 645 bayonet mount. It offers a built-in leaf shutter, which enables flash synchronization at all shutter speeds, a significant advantage for studio and location work where you need to overpower ambient light. The 240mm focal length translates to roughly 190mm in full-frame terms, making it a solid choice for portraiture, product work, and detailed capture at a comfortable working distance.

Schneider-Kreuznach has a long-standing reputation for high-end optical design, and the Blue Ring LS series is positioned as their autofocus-capable leaf shutter line for modern digital medium format systems. At this price point and with this mount, the lens is clearly aimed at working professionals who need the unique benefits of a leaf shutter and the resolution to match medium format sensors. The built-in hood and 86mm filter thread are practical touches for field use.