New Metabones 0.50x Speed Booster for Pentax Q (0.5x magnification and world-record f/0.666)

Metabones released a new 0.50x Speed Booster adapter for the Pentax Q mirrorless camera. It’s called the “Devil’s Speed Booster” because it permits a world record f/0.666 lens speed when a f/1.2 lens is attached. Even “ordinary” f/1.4 lenses will give you f/0.7 output.

Metabones adapters are sold at Amazon and B&H.

Metabones Nikon G to Pentax Q Speed Booster Q666 0.50x specifications:

  • Model Code:  MB_SPNFG-Q-BM1
  • Color:  Black Satin exterior; Black Matte interior
  • Magnification:  0.50x
  • Crop Factor for Pentax Q, Q10:  2.8x
  • Crop Factor for Pentax Q7, Q-S1:  2.3x
  • Maximum Output Aperture:  f/0.666 (with f/1.2 lens attached)
  • Rectilinear Distortion:  < 0.666%
  • Lens Elements/Groups:  6/4
  • Length Reduction:  10.1 mm
  • Supported Cameras:  Pentax Q, Q10, Q7, Q-S1
  • Camera Mount:  Pentax Q-mount
  • Image Format:  7.44 mm x 5.58 mm (1/1.7”)
  • Lens Mounts:  Nikon F/G
  • Lens Compatibility:  Any full-frame (36 mm x 24 mm format) or DX format (APS-C) lens with the appropriate mount can be used.
  • Special Features:  Long-throw clickless aperture ring on Nikon F/G version
  • Dimensions: 27 x 76 x 72mm for Nikon F/G version
  • Weight: 193 grams for Nikon F/G version
  • Tripod Mount:  Robust removable type with Arca Swiss compatibility

Press release:

Metabones Devil’s Speed Booster Q666 0.50x Press Release

Petersburg, VA, USA, Aug 30, 2017:  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.

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  • PavelR

    LOL – WR f0.666 – do you consider 4mm FL of lens for small chips as Wide Angle record? I do not think so.

  • Aren’t these Q cameras discontinued already?

    • PiDicus Rex

      Like most things Pentax, they’re just hard to find because the Canon/Nikon fanbois in the retailers are more interested in the bonuses Canon & Nikon pass the stores, so they direct sales to ‘the better (yah, riiight) brands, and people end up believing Pentax doesn’t exist,… Meanwhile, in real tests, Pentax kicks the butt of the competition for quality output At-Any-Price-Point.

      • Oh, a Pentax fanboi talking trash about Canon/Nikon… 😉

        • PiDicus Rex

          YEP! 🙂

          (Also,DXOMark rankings 😉 )

      • Zos Xavius

        They have been discontinued in the united states. Try to find it on the US web page.

        • PiDicus Rex

          “Not Sold Market X” and “Discontinued” are two very different things.

          One implies the the product is not available, the other is that it’s not made.

          Given all the crappy reports coming from a single Japanese newspaper during 2017, it’s wiser not to use ‘discontinued’ anywhere, even though all the CaNikon salespeople want buyers to believe it already.

          • Barbu Mateescu

            I would really enjoy buying a Q-S1 (or even the original Q) with a 01 Standard lens (or almost any lens, including the toy one). Can’t find any, not even on the second-hand market in Europe.
            I’m open to imports too, putting an overseas order, straight from Japan or anywhere I could find one.
            Sadly, it is *discontinued* even if the manufacturer really tries to avoid using that term.
            I use Pentax and (at least) two other brands. No fanboy here, enjoying all kinds of products, couldn’t care less about the logo printed on them.

          • PiDicus Rex

            Last I saw, there was still one or two in stock here.


  • PiDicus Rex

    Okay, lets be honest, how Ignorantly Stupid is it, for them to offer a Speedbooster for the baby Pentax camera, and have it only work with Nikon lenses ??

    IFF they plan multiple versions, the FIRST one released should have been for the Pentax K-mount lenses, which Most Q owners will already have.

    • Mistral75

      Metabones have other adapters for lenses in Nikon F/G mount and none for lenses in K mount. It was therefore easier for them to release first the Nikon F/G version of their Devil’s Speed Booster.

      • PiDicus Rex

        Last I spoke to someone in sales at Metabones, asking about a K-mount to E, or K to M4/3rds, speedbooster,… which would only involve changing the front flange to the correct lug shape from the C/Y to E or C/Y to M4/3rds units (K and C/Y have identical FFD),…. I was promptly told that Metabones had no interest in supporting K-mount lenses.
        This was in 2015.

        Now, ask this,… are Pentax Q owners more likely to have Pentax K Mount lenses for their other cameras, of Nikon lenses?

        So what would sell more units, a Speedbooster for a Q that matches the lenses the owners are most likely to have, or a Speedbooster for a Q for lenses that owners are not likely to have?

        This is just crap market research by Metabones.
        And I’d bet on them releasing an EF one before C/Y, and then dragging their feet on K-mount.

        • Practicalbuilds

          PiDicus Rex. Both K&F and Metabones gave me the same song and dance. Which makes this Q-mount offer even more of either an insult or a masterful stroke of imposing confusion. How do these companies marketing departments work? There doesn’t seem to be any logic what so ever.

        • Daedbird

          Umm, its right in the release that they plan on building a K-mount version of this, so happy days? Also, I think this continues to make me hate that the Q line doesn’t have a mic port on the camera, because if it did, I would have like two of them, instead of none…..because this would be a perfect item for a cheap low light vid rig

          • PiDicus Rex

            Just mount a Tascam DR-10SG or the like on the side of the tripod 😉

          • Shaepour

            especially for some Nikoners wishing to add a Pentax Q to their inventory so they can use their existing lenses with such a camera i guess …

    • Shaepour

      maybe for some Nikoners wishing to add a Pentax Q to their inventory so they can use their existing lenses with such a camera?

      • PiDicus Rex

        They’re more likely to buy a Nikon1 then a Pentax Q

        • Shaepour

          yes, certainly … but there are many people owning both Nikon and Pentax (and other) cameras and lenses …

          there are also older Pentax Q cameras that can be bought at a fraction of the price of a Nikon1 so as to be used as a second or third and so forth camera in a video shoot, for which apparently Pentax QS1 does a great job at smooth continuous focusing in video mode which amazes me too btw …

          maybe Nikon1 and possibly even bigger Nikon cameras don’t do that and there’s a demand among Nikoners (and Canoners) for the Pentax Q then? (check the video below past the 5:55 mark please … both the continuous focusing as well as video image quality is quite fine, especially in low light …)

          • Shaepour

            btw, checking prices online, apparently Pentax QS1 is being sold more expensive than the Nikon1 … a little bit curious … or maybe it’s worth it after all? have to check the latter’s specs and reviews to find out …

          • PiDicus Rex

            Yeah, but,…

            The point for Continuous AF doesn’t matter if owners are using Nikon lenses.

            And yes, I’ve thought about it as a B-cam for my K-01’s – it’s also ideal to have a ‘pro’ quality camera that goes through customs without questions about entering places as a commercial photographer.

    • Spy Black

      Has Metabones ever made any Pentax adapters? If not that explains a lot. They’re just improvising from their parts bin to make a toy for Nikon users to play with.

      • PiDicus Rex

        Again, the odds of Nikon owners buying a Pentax Q, are incredibly small.

        Frankly, they would make more sales to Nikon owners with a version that works on the Nikon1 series, just as they’d sell more to Q owners with a K-mount front end.

  • Ron Hendriks

    Oh I don’t see many users waiting for this.

    • Zos Xavius

      I know right?! With the crop factor alone this has really limited use, though I think this does at least reduce the factor to like 2.4x or something.

    • Shaepour

      how `bout Nikoners wishing to add a Pentax Q to their inventory so they can use their existing lenses with such a camera?

  • Shaepour

    something tells me this is more aimed at Nikoners wishing to add a Pentax Q (or two?) to their inventory so they can use their existing lenses with such a camera, right?

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