By site editor Dan Chung:

The Metabones Speedbooster has proved to be a popular item with many shooters looking for a large sensor look on smaller APS-C, Super35 and M4/3 sensors. This is accomplished by using an optic in the adapter to condense the size of the image exiting your lens so that it covers a smaller area – which in turn increases the amount of light hitting the sensor area by one f-stop.

The latest version now allows users of Nikon lenses to mount them onto NEX and Micro 4/3 cameras, giving a 0.71x wider field of view than if they were attached with a regular (non-optical) adapter. There is a clicked aperture ring on the adapters than allows manual adjustment of aperture on newer G lenses that otherwise have no aperture control. This ring is marked so aperture settings can be easily repeated.

I’ve been using the EOS to NEX version of the Metabones adapter for a while now and have found it to be extremely useful. It does however require careful paring, some lenses work brilliantly. Much of our recent coverage of Broadcast Asia was shot by Clinton Harn using the Speedbooster with Zeiss ZE lenses on an FS700. Some Canon lenses work well too, but others such as my 24-105mm F4L tend to vignette a bit too much for my taste. There doesn’t seem to be much info out there online at the moment to tell which lenses vignette and which don’t – you need to try them out for yourself. Even so if you are using NEX or M4/3 cameras I would recommend getting one as they are incredibly useful to have around. The new Nikon versions will certainly be finding their way into my camera bag if they are the same in quality as the EOS one.

Features as listed by Metabones:

Industry’s best aperture ring covers a 8-stop range with half-stop clicks. Markings show actual number of f-stops. No more guesswork! (Patent pending)

Increase maximum aperture by 1 stop.

Increase MTF.

Makes lens 0.71x wider.

Optics designed by Caldwell Photographic in the USA (patent pending).

The tripod foot is detachable and compatible with Arca Swiss, Markins, Photo cam ball heads.

Tips: Before mounting your lens to the adaptor, please make sure that the f-stop of aperture ring in the adaptor is turned to “8” (i.e. mounting your lens to the adaptor while only the aperture ring in the adaptor is full open.).

You can order the new Speedboosters now on the Metabones website.