- Increase maximum aperture by 1 stop
- Increase MTF of any lens attached
- Makes lens 0.71x wider
- 5-element/4-group optical design incorporating ultra-high index tantalum-based optical glass
- Supports 16:9 video with DX lenses
- Autofocus
- Iris/aperture controlled by the camera body
Like the ULTRA series for Sony E-mount, the Speed Booster ULTRA m43 uses an advanced 5-element 4-group optical design incorporating ultra-high index tantalum-based optical glass.
However, the ULTRA design makes very effective use of exotic materials at the furthest limit of glassmaking technology, and as a result is almost perfectly corrected for use with all full frame SLR lenses regardless of aperture. The Speed Booster ULTRA m43 will also work extremely well with many DX and APS-C format lenses provided the image circle of the lens is large enough.