Update – More About The Metabones Speed Booster (Guess Which Is The FF Cam!)

Update: According to Japanese site dc.watch.impress the Metabones Speed Boost adapter will be on sale in Japan at the end of January 2013.

Update2: click here to read Metabones' white paper about the Speed Booster adapter. 30 pages of tech talk.

More About The Metabones Speed Booster. EOSHD did some simple but effective tests with Metabones' amazing Speed Booster adapter (we reported here). In short: the Metabones Speed Booster makes a lens wider and faster. Sounds like voodoo? It isn't, just clever engineering. To give a visual aid to what the adapater promises to deliver, have a look at the following two images. Only one was shot using a full-frame DSLR.

More About The Metabones Speed Booster

Image courtesy: EOSHD

Did you guess which pic was shot with the full-frame camera? Both pics were shot using a Sigma 24mm F1.8 (price & specs). The top one using a Sony NEX-7 (price & specs), the bottom pic using a Canon EOS 5D Mark III (price & specs)

As you can see the field of view is as good as identical. Quoting EOSHD: “The Speed Boost effect on aperture is highly evident too. On the NEX 7 the camera reports the maximum aperture as F1.3 and it is certainly brighter. […the] “depth of field is as shallow on the NEX 7 as the 5D Mark III despite the difference in sensor size.

I agree with the following statement: “This is a groundbreaking product for photographers and cinematographers alike.” The EOSHD post has more samples to check and an exhaustive description on how this wonder thing works.

A synthetic description how the adapter works: “If your sensor is smaller than full frame, shrink the image that the lens throws to fit over it. That is the principal behind the Metabones Speed Booster which essentially gives you the full frame look and a brighter image all at once…

With this adapter:

  • A 24mm wide angle like the Canon 24mm F1.4L becomes a 24mm wide angle on the Sony FS100 (price & specs), with the same shallow DOF and field of view as on the 5D Mark III

  • A F1.2 aperture on a Canon lens becomes F0.90, a significant 1 stop brighter image in low light

  • Depth of field becomes shallower – the same as it would be on full frame

[EOSHD via Fujirumors]


  • Bob B.

    So…a given FF lens on a FF camera will exhibit the exact same Image Frame (perspective), and DOF on a crop-sensor mirrorless camera when coupled with the Metabones adapter, but the adapter allows you to shoot at a lower ISO on the crop-sensor mirrorless with this lens to get the same exposure value?
    I wonder how much the glass lens in the adapter effects the optical quality of the given lens….there has to be some affect, no?

  • DW

    All lenses would be manual focus though correct? What about putting a Canon FF lens on a Canon M, would that be able to auto focus?

    • Bob B.

      DW .. if you want to put an EF lens on the M, the entire Canon EF and EF-S lens catalogue is supported with autofocus and auto exposure using the optional EF-EOS M adapter. Image Stabilization is supported, too. The EF lenses would have a 1.6x factor on the M. ie. a 50mm EF lens would preform ~like an 80mm.
      Not sure how fast the AF is though.
      I think I have this explanation correct. I do not own an M or the adapter.

  • B B

    Can this adapter only be used on mirrorless or any camera that can take EF lenses that have smaller than a full frame sensor?

    Also correct me if I’m wrong. Lets say I have a 7D + this adapter + 50 1.2. Does that mean with it my FOV will be 50mm (instead of 80mm) and I’ll gain 1 stop of light (f/0.9)?

    Pretty cool nonetheless if you don’t mind MF.

    • Admin

      35mm and f/0.9

      • Bob B.

        Frank…this is really confusing. So, according to the article above: A 50mm f/1.2 lens acts like a 35mm f/.09 S lens on the 7D. So in effect the 50mm f/1.2 with the Metabones adapter has the same effective FOV on the 7D as it does on a 5DIII, i.e. 50mm equivalent with an effective aperture of f/0.9. ?
        To say this another way: If I put the EF 50mm f/1.2 L with the Metabones Adapter on a 7D (or a NEX) my image in the viewfinder will look EXACTLY the same in the viewfinder on a 5DIII, the image on the 7D will have exactly the same DOF as the image on 5DIII, BUT the 7D will effectively get more light to the sensor so I could shoot at a lower ISO with the 7D (and record the same image as the 5DIII).?? Of course the image has been recorded on a smaller sensor on the 7D exposure.
        I am trying to get this straight in my head.

  • Josh

    It only works on mirrorless cameras and only on crop sensors.

    It effectively magnifies the image by reducing the size of the image circle. It’s sort of like they moved the lens forward a little and let the light converge more. The glass is there to correct for the distortion caused by doing this.

    About the lens, yes, a 50mm on crop will give almost the same FOV and DOF as a 50mm on FF. Also, this adapter must be used with FF lenses only (for sony cams at least).

    Yes, autofocus is supported but it’s only contrast detect.

    • Bob B.

      Thanks Josh…I get it …you cannot use and adapter like this on a camera with a mirror on it because the lens mount is too far from the film plane, right?
      I think I understand this…but I didn’t read anything about the Metabones that said that some of the adapters were supporting autofocus. I thought that they are all manual focust only?