Like the original Speed Booster, the ULTRA still has the same feature set in that it widens the field of view by 0.71x — which effectively allows for a full-frame field of view on s35-sized sensors — and it provides an extra stop of light. However, what sets the ULTRA apart from its predecessor is a major boost in optical performance, which is derived from incorporating highly improved optical elements made from ultra-high index tantalum-based optical glass into the manufacturing process.

Here's what Metabones has to say about the new adapters in their recent press release:

The new ULTRA design makes very effective use of exotic materials at the furthest limit of glassmaking technology, and as a result is well corrected for use with virtually all fullframe SLR lenses regardless of exit pupil distance. Thus, the Speed Booster ULTRA performs extremely well with professional-grade f/2.8 zoom lenses such as the 24-70mm f/2.8 and 70-200mm f/2.8 zooms by Canon and Nikon to produce 17-50mm f/2.0 and 50-142mm f/2.0 high-speed zooms, respectively. Similarly, high-speed fixed focal length lenses such as a 50mm f/1.2 will be transformed into a 35.5mm f/0.9 lens with excellent contrast and resolution from the center all the way to the edges of the image.

Metabones Speed Booster Canon EF to NEX Speed Booster ULTRA Flat

With the new Speed Booster ULTRA, you can expect optical performance to vastly improve in a number of areas, chiefly in corner-to-corner sharpness, vignetting, and various types of optical distortion.

The Speed Booster ULTRA models are available to buy right now from the Metabones website, so it shouldn't be long before we see them in the wild. How much cash will a Speed Booster ULTRA set you back, you ask? Luckily, not much more than the original Speed Booster:

  • US $450 for Olympus OM, Rollei QBM, Minota MD, Leica R, Canon FD, Contax Yashica mounts
  • US $480 for Nikon G, Sony A mounts
  • US $500 for ALPA, Contartex mounts
  • US $650 for Canon EF to NEX mount

We'll keep you guys updated with all of the latest news on the Speed Booster ULTRA, especially once we start to see footage shot with the new device.

Source: Metabones Speed Booster