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M42 & Kmount adapter that stops down

Discussion in 'Adapted Lenses' started by usayit, Jul 11, 2010.

  1. usayit

    usayit Mu-43 Hall of Famer

    So far, all my M42 adapters are simply tubes of proper length with M42 screwmount on one end and a Micro 4/3rds mount on the other. I open up and stop down the lenses via the M-A switch on my Takumars.

    I do have a few M42 lenses (Sigma for example) that do not provide a way to manually stop down the aperture. Does anyone know of any M42-m4/3rd adapters that are designed with either a switch to push the aperture pin in or do so when the lens is mounted?

    How about for K-mount lenses... Any PK adapters designed with a switch to open and close the aperture diaphragm for easier critical focus?

    side note:

    Today I went to a camera swap and was surprised to find a Minolta AF to m4/3rd adapter for $1 (somehow got included in a junk/rummage pile. The seller didn't know what it was). This particular adapter has a ring that rotates to engage the aperture lever in the lens mount. I'm hoping to find something simlar.
  2. usayit

    usayit Mu-43 Hall of Famer


    Still hoping for at least an M42 adapter that pushes the aperture pin inward to force the lens stopped down.
  3. DarthBalls

    DarthBalls New to Mu-43

    Sep 2, 2011
    I have also been trying to find the same thing. My wife has a 16mm f2.8 Sigma for her Prakticas that I'd love to put on my EP-1, sadly the Sigma has no A/M switch.
  4. usayit

    usayit Mu-43 Hall of Famer

    Unfortunately, the only adapters I've found that can stop down lenses are for various Nikon mount and Minolta AF mount. Still haven't seen any capable of stopping down K or M42.

    Thanks for searching/finding and bumping this thread to the top; its been a while maybe an option is out there now and someone will respond.
  5. DarthBalls

    DarthBalls New to Mu-43

    Sep 2, 2011
    Yeah - I certainly hope so. I just bought a Kiwi adaptor off Amazon to use with the 55mm.
  6. Re the M42 adapter: Do you mean whether the adapter has an additional ring/plate in the middle to push down the pin at the back of the lens? I bought an M42-EF adapter where you could choose to purchase it either with or without. I also bought a Fotodiox M42-4/3 adapter as part of package which did not have the additional plate and leaves you stuck with using the lens wide-open. Either adapter can be used on my m4/3 cams when stacked with another, but the second (fotodiox) is a bit useless without aperture control.

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  7. KVG

    KVG Banned User

    May 10, 2011
    yyc(Calgary, AB)
    Kelly Gibbons
    I have bought 2 ebay ones that have that.
  8. WJW59

    WJW59 Mu-43 Veteran Subscribing Member

    Feb 20, 2011
    • Like Like x 1
  9. usayit

    usayit Mu-43 Hall of Famer

    Thanks just ordered one via amazon. If its adequate, probably buy a second. Now of I can find a m42 adapter thats like the 43 one luckypenguin mentioned, Id be set. I am not too keen about buying two and stacking.
  10. gscara

    gscara Mu-43 Regular

    Pentax K mount lenses

    Pentax K mount lenses don't need any special adapter when they are mounted on micro 4/3 adapters. These lenses will open and close when you change the aperture ring. When these lenses are mounted on pentax cameras, the pentax camera will hold the lens wide open until the shot is taken.

    Only newer pentax auto focus lenses, typically DA series, need to have aperture control built into the adapter as they don't have manual aperture control rings.
    • Like Like x 1
  11. WJW59

    WJW59 Mu-43 Veteran Subscribing Member

    Feb 20, 2011
    The FA-J lenses also lack an aperture ring. But this adapter should allow you to change the aperture on the FA-J/DA lenses by turning and holding the ring, so shooting at the minimum aperture won't be the only option with these lenses. The default aperture position on the FA-J/DA lenses is the minimum aperture and most of the K adapters don't seem to have any sort of lever to keep the aperture open. This would also be true of an K A lens when set to the A position.
  12. usayit

    usayit Mu-43 Hall of Famer

    In addition to what WJW59 said,

    Ideally, you want to focus with the lens wide open and then stop down for exposure. Its not just about controlling the aperture setting. Yes, you can do accomplish this by turning the aperture ring wide open then to a stop of your selection. This requires either a to turn of the ring (while looking at the lens) OR start counting stops as you rotate the aperture ring (while looking through the viewfinder). Neither is ideal as it disrupts the act of composing a photo.

    For M42 lenses, it is true that Takumars have the A-M switch that allows you to quickly to open and stop down the lenses but not all M42 lenses of different makes have this feature. For these lenses, you can only shoot wide open which is extremely limiting. An ideal M42-Micro 43 adapter would allow one to turn a ring or switch to stop down rather than depend on the lens implementing this feature. Basically, I'm looking of the same operation as the side switch on my old Spotmatics which a mechanism pushed the pin on the mount.

    For K-mount lenses, the lens is always stopped down. It requires me to turn the aperture ring wide open, focus, and then set the aperture ring back to position for exposure. This is very cumbersome. If you don't want to disrupt the framing (removing the camera from eye level), you have to start counting clicks on the aperture ring (slow). In particular, macro photography is next to impossible as you typically shoot at f/11 and smaller to obtain a workable DOF relying on a ring flash or macro flash. At f/11, there isn't enough light for the EVF to work properly and focusing becomes very difficult.

    This is one of the advantages of using Pentax DSLRs over Micro 4/3 for K-mount lenses. They still have the mechanical linkage that automatically stops the lens down at the time of exposure allowing wide open aperture for focusing.
  13. usayit

    usayit Mu-43 Hall of Famer

    Just as a follow up.

    The Fotodiox K-mount to M43 adapter with the diaphragm ring came in today.

    * Quality is on par with all the adapters of the similar price range. Bent metal flanges rather than "leaf" springs BUT perfectly fine.
    * Lens attaches with no play.
    * Lens to adapter release lever has a nice positive feel.
    * Locks into place quite nicely on the camera (Panny G1 and E-PL1). No play there either.

    My only complaint (small)
    * Diaphragm ring doesn't have much of a grip. A bit slippery and my fingers slide as I try to open and stop down the lens. I couldn't turn it easily with a single finger. I stuck a rubber "dot" on the ring so I can operate it with my left hand thumb rather quickly. Now it works like a charm.

    Just what I was looking for! Now if I can find a M42 screwmount version.
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