Much talked about and highly anticipated Canon EF to Sony E Mount adapter that makes your lenses wider and faster. Essentially it is a reverse teleconverter that you normally use to extend the focal length of your lenses.
- Increase maximum aperture by 1 stop.
- Increase MTF.
- Makes lens 0.71x wider.
- Electronic integration of aperture diaphragm, controlled by or from the camera body.
- Partial autofocus support for late-model (post-2006) Canon-brand lenses.
- Powered by camera body. No external power source required.
- 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.
These lenses and functions are officially supported by this adapter:
- EF lenses
- Image stabilization (IS)
- Electronic manual focusing (e.g. EF 85/1.2L II and discontinued EF 50/1.0L)
- EXIF (focal length, aperture, zoom range)
- P, A, S, M exposure modes
- Autofocus (see autofocus support section below)
- Distance and zoom display on VG and FS series camcorders (see note 1)
- Auto magnify (see note 1)
- Contax N mount lenses modified to Canon EF by Conurus (see note 2)
- Contax 645 NAM-1 adapter modified to Canon EF by Conurus (see note 2)
- Sigma, Tamron and Tokina lenses in Canon EF mount (see note 3)
- Requires lenses supporting distance information.
- Autofocus disabled for Contax N and Contax 645 lenses.
- A third party zoom lens may need to be registered with the Smart Adapter first in order to detect its maximum aperture. Autofocus is disabled for most third-party lenses.
- This Speed Booster™ is designed to cover an APS-C image circle which is not big enough to cover a full-size 36mm x 24mm sensor.
- Sony NEX cameras cannot display aperture values beyond f/1.0. If a f/1.2 Canon EF lens is used with the Speed Booster™, the resulting aperture is f/0.9 but the camera body displays f/1.0.
- 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.
- 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™. They need to be modified before they can be safely used on Speed Booster™. 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™ are not covered by warranty.
- Super-telephoto lenses such as the Leica-R Telyt 560/5.6 may have significant vignetting in the corners.
Autofocus is supported, with the following known limitations.
- Autofocus speed is very slow and inadequate for most moving subjects. The autofocus speed is unfit for professional use for sure, and it would disappoint most enthusiasts.
- Only Canon-branded lenses introduced in or after 2006 are officially supported. Autofocus is disabled for older Canon lenses and most third-party lenses, including most Sigma, Tamron and Tokina lenses and all Contax N lenses modified by Conurus.
- On NEX camera bodies in camcorder form factor (e.g. FS series), autofocus may be available only in photo mode but not in movie capture mode.
- Continuous AF is not supported.
- DMF mode (direct manual focus) is not supported.
- For non-camcorder camera bodies (e.g. NEX-7), during movie capture, if the subject moves to a different distance, half-press the shutter release button to re-activate autofocus and lock onto the subject again. Since autofocus speed is slow, there may be visible disruption in the resulting footage.
- The first two autofocus attempts are used to calibrate the lens and as a result may not lock successfully on the target. Half-press the shutter release button again and autofocus will lock successfully.
- Autofocus may have difficultly locking onto subjects which are very close to the nearest focusing distance of the lens.
- Autofocus accuracy depends heavily on the working condition of the lens. Lenses with hidden problems which may not be apparent on Canon DSLRs will lead to inaccurate and unreliable autofocus on Sony NEX. Typical problems of this kind that we have seen include an unsmooth/erratic autofocus mechanism (e.g. getting stuck intermittently at a certain focusing distance), a faulty/worn-out distance encoder or other faulty/worn-out internal sensors.