Metabones Leica R to Sony E Speed Booster ULTRA 0.71x (MB_SPLR-E-BM2)

Optical Design and Performance

• Advanced 5-element/4-group optical design incorporating ultra-high index tantalum-based optical glass.
• Designed by Caldwell Photographic in the USA (patent pending) to achieve extraordinary optical performance.
• Improved corner sharpness, reduced distortion, and minimized vignetting.
• Magnification factor of 0.71x effectively widens lenses and reduces crop factor from 1.5x to 1.07x on DX-sized sensor mirrorless cameras.
• Increases maximum aperture by 1 stop and improves modulation transfer function (MTF).

Compatibility and Usage

• Designed for Leica R lenses adapted to Sony E-mount mirrorless cameras.
• Compatible with full-frame SLR lenses regardless of exit pupil distance.
• Performs well with professional-grade f/2.8 zoom lenses (e.g., 24-70mm f/2.8, 70-200mm f/2.8) and high-speed prime lenses (e.g., 50mm f/1.2 transformed to 35.5mm f/0.9).
• Note: Some Leica R lenses require modification to fit (Super-Elmar-R 15mm, Elmarit R 28/2.8, Elmarit R 35/2.8, Summicron R 50/2).
• Super telephoto lenses such as Telyt 560/5.6 may vignette at the corners.

Electronic and Mechanical Features

• True electronic integration of aperture diaphragm allowing automatic aperture control in P or S modes and manual control in A or M modes.
• Supports EXIF data transmission, image stabilization, and autofocus functionality.
• Powered solely by the camera body; no external power source required.
• Wide open button facilitates manual focusing by temporarily opening the aperture fully.
• High-performance 32-bit processor with efficient switched-mode power supply.
• Flocking material coating inside the adapter reduces internal reflections to maintain optical quality.
• Detachable tripod foot compatible with Arca Swiss, Markins, and Photo Cam ball heads.

Build Quality and Materials

• Precision-machined brass construction with chromium plating on both camera-body and lens sides for durability and smooth mounting.
• Strong leaf-spring structure on lens side ensures tight lens connection, reducing wear and preventing focus errors and optical misalignment.
• Matte-black internal treatment minimizes reflections to preserve image quality.
• Robust processing and outstanding finish consistent with Metabones' reputation for professional-grade adapters.

Disclaimer

• Metabones is not licensed, approved, or endorsed by Sony or Leica.
• Some lenses may require modification to fit the adapter properly.
• Super telephoto lenses may exhibit corner vignetting.