Metabones—the company known for its lens adapters and focal reducing Speed Boosters—has released a new Speed Booster that ought to have Pentax Q users salivating a bit. It’s called the Q666 0.5x ‘Devils Speed Booster’, because it allows Pentax Q owners to mount Nikon F and G lenses and produce a working aperture of f/0.666 when a lens with an f/1.2 aperture is used wide open.
The booster has a magnification of 0.5x and produces a 2.8x crop factor when used with the Q and Q10, and a 2.3x factor with the Q7 and Q-S1.
Metabones has used six elements in four groups inside this new Speed Booster, and has incorporated what it calls a ‘long-throw clickless aperture ring’ for G lenses that has eight marked positions. The adapter is compatible with all Nikkor and Nikon-mount lenses except the Nikkor 2.1cm f/4 and the 20mm f/2.8 AI-S.
The idea for the adapter was launched in August, but this is the first version to emerge. Metabones promises one for Pentax K mount lenses as well.
The Metabones Nikon G to Pentax Q Speed Booster Q666 0.50x costs $490. For more information, visit the Metabones website.
Metabones Devil’s Speed Booster Q666 0.50x
Caldwell Photographic Inc. and Metabones® is pleased to announce the Speed Booster Q666, a.k.a. “The Devil’s Speed Booster”, exclusively for Pentax Q series cameras. With its 0.5x magnification and world-record f/0.666 maximum speed it is crazy wicked fast. So make a deal with the devil today and turn your Pentax Q with its back-illuminated sensor into a monster low-light machine unlike anything ever seen in photography. Attach an f/1.2 lens and stop down a little to see how Stanley Kubrick made do with f/0.7 for filming those famous candle-lit scenes in “Barry Lyndon”. Or open up all the way to f/0.666 and probe the darkness in a way that no photographer has ever been able to do until now.
With an advanced 6-element optical design, the Q666 packs lots of optical horsepower in a small package. Sharpness is excellent even at f/0.666, and is downright superb if you stop down to f/1.0. Distortion is very low, with a maximum value of, naturally, 0.666%. And thanks to the back-illuminated sensor used in Pentax Q cameras, the full f/0.666 maximum aperture can be utilized with minimal pixel vignetting effects commonly seen in other cameras used with high-speed lenses.
Figures 2 through 4 below show MTF at 10, 20, and 40 lp/mm as a function of image height for output apertures of f/0.666, f/1.0, and f/2.01. At f/0.666 (i.e., with an f/1.2 master lens) the MTF is high near the axis, and only falls off gradually toward the corners. As the aperture is reduced to f/1.0 and then f/2.0 the MTF becomes very high and more even across the field. Figure 5 shows that there is less than 1 stop of corner illumination falloff even at f/0.666. And guess what – there is no vignetting at all after the output aperture reaches f/1.82. Figure 6 shows that rectilinear distortion added by the Speed Booster Q666 is negligible at less than 0.666%.
Like all Metabones Speed Boosters, the Speed Booster Q666 is optimized to fully account for the camera’s filter stack located near the sensor surface. This is especially critical at the record-setting f/0.666 aperture now possible with the Q666. As a result, an enormous range of optics, from vintage film lenses to the latest digital designs, will function flawlessly when adapted to any Pentax Q camera. Planned lens mounts for the Speed Booster Q666 include a Pentax-K version and a Nikon F/G version with the most advanced Nikon G aperture adjustment mechanism in the industry.
The Speed Booster Q666 will be available starting in Aug 2017 from the Metabones website (http://www.metabones.com/products/details/MB_SPNFG-Q-BM1) and its worldwide dealer network for US $489.00, plus shipping and applicable taxes and duties.