• Increase maximum aperture by 1¹/₃ stop. (with a maximum output aperture of f/0.80)
• Increase MTF.
• Makes lens 0.64x wider.
• Optics designed by Caldwell Photographic in the USA (patent granted).
• When using with "passive" (without electronic control pin) MFT camcorders/cameras, such as BMCC 2.5K MFT and Digital Bolex D16 MFT, the Speed Booster must be powered by external power source via Micro-USB socket. Input Voltage is 5V DC.  (Battery is NOT included in the box).
• When using with "active" (with electronic control pin) MFT camcordrs/cameras, such as BMPCC MFT, the Speed Booster can be powered by camera body. no external power source required.
• Build-in electonics to control lens aperture. 
• The Lens aperture is set by the dial button on the adapter.
• High performance 32-bit processor and efficient switched-mode power supply.
• The tripod foot is detachable and compatible with Arca Swiss, Markins, Photo Clam ball heads.
• Flocking material coating inside the inner hole to reduce the internal reflection.

Canon EF to BMCC mount T Speed Booster^TM  adapters designed exclusively for the Blackmagic 2.5k Cinema Camera (BMCC). Note that the new Speed Boosters will only attach to Blackmagic cameras equipped with a Micro-4/3 mount.  They cannot be attached to standard Micro 4/3 cameras.

The new 0.64x Speed Booster reduces the full-frame crop factor of the BMCC from 2.39x to 1.53x, thus effectively transforming it into a Super-35 format cine camera.  In addition, the speed of any attached lens is increased by 1¹/₃ stops, with a maximum output aperture of f/0.80.  

Note:

1. Requires lenses supporting distance information.
2. A third party zoom lens may need to be first in order to detect its maximum aperture. 
3. This Speed Booster is designed to cover an BMCC image circle which is not big enough to cover a full-size 36mm x 24mm sensor.

4. For use with fast lenses (faster than f/1.8), the pre-boost apertures will be displayed in the camera.

   Slow lenses will report boosted apertures to the camera body but fast lenses will report pre-boost apertures. We won't show f/0.7 with a f/1.2 lens attached, but show f/1.2 instead. 

   Example:

   a) EF 85/1.2L attached, camera display = f/1.2, physical aperture  (lens + Speed Booster combined) = f/0.74.
   b) Sigma 18-35/1.8 attached, camera display = f/1.0, physical aperture (lens + Speed Booster combined) = f/1.0.

5. Some improperly-made M42 screw mount adapters may short the electronic contacts of the Speed Booster and cause damage to the Speed Booster and/or camera body.
6. Many manual focus lenses (e.g. OM 28/2.8, OM 50/1.8, Leica R 15/3.5) have rear protrusions (spikes, levers, other appendages) which would damage the optics and/or housing of Speed Booster^TM They need to be modified before they can be safely used on Speed Booster^TM Check and make sure there are no rear protrusions from the adapter/lens combination before using on Speed Booster. Scratches and damages caused by rear protrusions on Speed Booster^TM are not covered by warranty.
7. This Speed Booster may NOT be fully compatible with GH4 or other MFT camera. This is use only with BMCC or BMPCC. When Speed Booster® is used with other MFT camera, it may cause damage on the camera.

List of lenses (have been tested by metabones) with support on EF-BMCC Speed Booster.

List of manual focus lenses which REQUIRE MODIFICATION to be used on Speed Booster

Many manual focus lenses have rear protrusions (spikes, levers, other appendages) which would damage the optics and/or housing of Speed Booster^TM They need to be modified before they can be safely used on Speed Booster^TM Check and make sure there are no rear protrusions from the adapter/lens combination before using on Speed Booster. Scratches and damages caused by rear protrusions or by poor quality adapters are not covered by warranty. The following is an incomplete list of lenses known to be incompatible.