Why no teleconverters for Micro Four Thirds?

Discussion in 'Accessories' started by DeeJayK, May 24, 2012.

  1. DeeJayK

    DeeJayK Mu-43 Hall of Famer

    Feb 8, 2011
    Pacific Northwest, USA
    Real Name:
    Does anyone know of any teleconverters that have been released for the :43: system? I have never seen or heard of any.

    The release of the Olympus 75mm lens prompted my question. As the 75mm focal length is not one that I would find terribly usable, it's highly unlikely that I will ever own this lens (particularly considering the price). For me, a 1.7x teleconverter along with the Olympus 45mm would be a more practical, flexible 75mm solution. I realize that I'd lose 1-2 stops of light with a teleconverter, so this combination would not be as fast as the 75mm lens, but I think it would be fast enough for my purposes.

    Olympus offers teleconverters for Four Thirds, so I wonder if this is something they (or an enterprising third party) is likely to ever offer for the :43: system?
  2. blue

    blue Mu-43 Veteran

    Jun 1, 2010
    You've sort of answered your own question really. It is because there are no long fast lenses. Not sure the 75mm on its own would warrant it, maybe when we have the 35-100 2.8 there may be more demand ?
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  3. phrenic

    phrenic Mu-43 All-Pro

    Sep 13, 2010
    The recent release of the electronic extension tubes is a promising sign that we may see it in the future.

    Newb question here, but how do teleconverters affect DOF? Is there an equivalent loss to the loss of light?
  4. RevBob

    RevBob Super Moderator

    Jun 4, 2011
    NorthWestern PA
    Real Name:
    Not sure about DOF but I'm fairly certain there is a loss of light, at least one f-stop if not more on most converters.
  5. Amin Sabet

    Amin Sabet Administrator

    Apr 10, 2009
    Boston, MA (USA)
    A 75mm f/1.8 lens with a 2X TC physically becomes a 150mm f/3.6 when you consider the lens plus TC combination as a single, new lens.

    A 75/1.8 with a 1.4X TC welded on is a 105mm f/2.5.

    If the 75/1.8 is as good wide open as I'm hoping it will be, maybe we'll see some TCs emerge, if not from Olympus then from a third party.
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  6. DeeJayK

    DeeJayK Mu-43 Hall of Famer

    Feb 8, 2011
    Pacific Northwest, USA
    Real Name:
    I'm a bit of a newb myself, but my understanding is that "rule of thumb" is that you'll lose about 1 f-stop with a 1.4x and 2 f-stops with a 2x teleconverter. <strike>I don't think that the light loss impacts the DOF, since DOF is mostly a function of the size of the aperture. My understanding is that it just means you're have to keep the shutter open twice (for 1.4x) or four times (for 2x) as long to allow sufficient light for the exposure.</strike> However, I'll defer to the experts as they weigh in.

    EDIT: After reading Amin's reply and a little bit of Googling. I'm convinced that my thinking was incorrect and that teleconverters will have an impact on DOF commensurate with the light loss. Maybe next time I should try Google before I reply. :redface:
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  7. Amin Sabet

    Amin Sabet Administrator

    Apr 10, 2009
    Boston, MA (USA)
    If you take picture with the lens at max aperture before and after adding a 2X TC and don't move your feet (fixed subject distance), your DOF will be cut in half with the TC, but your angle of view (which determines framing) will also be cut in half (you will be zoomed in).

    If you take a picture with the lens at max aperture before and after adding a 2X TC but double the subject distance after adding the 2X TC, then the angle of view will be maintained (same framing) and the DOF will actually double with the use of the TC.

    As far as exposure is concerned, you lose 1 stop of with a 1.4X TC and 2 stops with a 2X TC.
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  8. dhazeghi

    dhazeghi Mu-43 Hall of Famer

    Aug 6, 2010
    San Jose, CA
    Real Name:
    I expect either Olympus or Panasonic will have one fairly soon.

    Teleconverters for telephoto lenses make sense and aren't especially difficult to make. Now that we finally have fast telephoto lenses from both manufacturers due out by the end of the year, there's actually a potential market for such TCs.

    I do suspect that due to the peculiar designs of m4/3 wide-angle lenses, any m4/3 TCs will probably not support them, unlike in the case of regular 4/3.

  9. phrenic

    phrenic Mu-43 All-Pro

    Sep 13, 2010
    Thanks for the explanations everyone. Hmm I'd love to see an option to pick up something like a fast 135mm or 150mm with a TC option. Could be a good alternative to the 100-300mm for occasional wildlife shots, presumably with faster aperture and better performance than a zoom. Though I guess prices would be way more given the 75mm/12mm as an estimate.
  10. Ned

    Ned Mu-43 Legend

    Jul 18, 2010
    Alberta, Canada
    Yup, I use my 1.4x teleconverter with my Zeiss 135mm f/2.8 all the time. I also have a 200mm f/4 which I love, but the 135mm/2.8 + 1.4x converter does the same thing but also allows me the option of going wider and faster. :) It is a very useful combination.
  11. ssgreenley

    ssgreenley Mu-43 Top Veteran

    May 12, 2011
    OH NO, EQUIVILENCY TALK?!?! I fear it has begun...

    Seriously though, a tc would be great, and would make the 75 a much more practical, versatile lens.
  12. RT_Panther

    RT_Panther Mu-43 Legend

    May 4, 2011
    I would very much like this. :smile:
  13. ~tc~

    ~tc~ Mu-43 Hall of Famer

    Oct 22, 2010
    Houston, TX
    If Panasonic comes out with a 2x TC, I will buy one and a 35-100/2.8 to replace my 45-200. Otherwise, the loss of long end is just too much.
  14. feilb

    feilb Mu-43 Regular

    Dec 4, 2012
    I imagine with the advent of Pany's 150/2.8, there will be increased demand for just such a device.

    A 1.4 with the 75 sounds interesting as well.
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  15. garfield_cz

    garfield_cz Mu-43 Veteran

    Jul 9, 2011
    Czech Republic
    Real Name:
    I don't need teleconverter ;) for amateur purposes I am satisfied with adapted old manual telephoto lens. In other words my Sonnar 135/3.5 is giving me impressive 270mm. I know f/7.0 after conversion is not very good, but sharpness remains unchanged, and it is producing pleasant pictures on good light conditions :thumbup:
  16. meyerweb

    meyerweb Mu-43 Hall of Famer

    Sep 5, 2011
    Your Sonnar is still an f/3.5 in terms of exposure. Only in DOF is it equivalent to a 270mm f/7 (or a 135 f/3.5).
  17. speedandstyle

    speedandstyle Mu-43 Hall of Famer

    I too have been wanting a tc for m4/3 and the new 75mm would be a perfect match for it. The 150mm when it comes would be even better. The sad thing is both the 75 and the 150 are(will be) pricey.

    If you used a 1.4tc on the 100-300mm f4-5.6 it would become a 140-420mm f5.6-8. This would be very usable for bright sunny conditions. It would be the equvilant of a 280-840mm in FF!
  18. dhazeghi

    dhazeghi Mu-43 Hall of Famer

    Aug 6, 2010
    San Jose, CA
    Real Name:
    I'd be more worries about sharpness in that case. A middling lens with a teleconverter often looks worse than simply cropping and upsampling an image taken using the lens without the teleconverter.
  19. Mogul

    Mogul Mu-43 Regular

    Nov 9, 2012
    Any increase in the focal length of a lens will cause a reduction in DOF. This includes TC's.
  20. Stephen

    Stephen Mu-43 Regular

    Jan 2, 2013
    I had a word with a lens design expert at the optical company I used to work for and teleconverters for micro 4/3 are very difficult to design, due to the short back element distances to the sensor, and the need for particular diameters of the elements, which would get in the path of the electrical contacts.

    The constraint is the electrical connections required for the native lens, they impinge on the diameter of the glass elements in a converter.

    It can be got around, with the connectors feeding a wiring harness to get by the glass and connect to the lens, but this would be expensive to do and might push the converter from general use cost to a specialist price level item.

    I think it more likely a maker like Panasonic or Olympus would offer a matching teleconverter for a particular lens, than for general purpose ones to appear.

    Converters can be used with legacy lens of course, as there is no other connection than the mount to worry about, no bank of electrical connections to make.

    Converters do reduce definition by the extension factor, but may still leave the apparent DOF seemingly untouched, most better lens can have the definition reduced without the shot looking at all bad.