- True electronic integration of aperture diaphragm - let camera automatically choose aperture in P or S exposure modes or dial in yourself on the camera body in A or M modes.
- Powered by camera body. No external power source required.
- Wide open button (opposite of depth-of-field preview function) makes manual focusing easy.
- The tripod foot is detachable and compatible with Arca Swiss, Markins, Photo cam ball heads.
- High-performance 32-bit processor and efficient switched-mode power supply.
- Flocking material coating inside the inner hole to reduce the internal reflection.
Enhancement on new MARK IV (MB_EF-E-BT4) vs. old MARK IV (MB_EF-E-BM4):
- The inner hole is painted with flocking material coating. This can further reduce the internal reflection.