M42 screw mount adaptor

Started Jan 12, 2013 | Questions thread
captura Forum Pro • Posts: 24,619
Re: M42 screw mount adaptor

hindesite wrote:

captura wrote:

hindesite wrote:

The Rainbow Imaging adapter may not the the correct one for your lenses.

The are several things to watch for.

Some adapters have no step inside the m42 thread. These will work with lenses that are fully manual (usually have a preset ring adjacent to the aperture ring) or with lenses which have a switch that switches the lens from "auto" to "manual" if you can set the switch to manual.

Many adapters have a ledge or flange inside the m42 thread, this depresses the pin that actuates the aperture on some lenses. If your lenses are auto, have the pin to close the aperture and do not have a switch, you will need one of these adapters.

Some lenses (some Takumar, for example) have additional pins and other features on the rear surface of the mount, and if the internal flange is too wide, it may interfere with the operation of the lens or prevent it seating and achieving infinity focus.

It's common to shorten those pins with a dremel tool or something.

Here's a tilt-shift adapter for m42 to m43 which might be interesting...


I'd feel bad about ruining the lens for somebody else in future. On my old 28mm Takumar, there is a rotating stub that indicates aperture back to the camera, and a raised land with a pin in it to disable auto/manual switch when the lens is off the camera (IIRC). It is better to get the right adapter for the lens, they don't cost much.

The tilt adapter looks good. Says infinity focus is achievable and if true this can also be used as a standard adapter. I'm almost tempted... thanks for the link.

My preference though would be for EF to m4/3, because AFAIK you can then adapt many lenses to the EF mount; or for PK to m4/3, because I could use both my m42 and PK mount lenses, but both of those tilt adapters are considerably more expensive than the m42 one you linked to.

I wouldn't want to modify a Takumar either; too nice, besides some of the radiation could leak out in an act of revenge on you!

But there are a number of articles on the weeb  about how to modify the mount on a (cheaper) Canon EF lens so it will simply go onto a NEX e-mount, without an adapter. (Presumably the same thing with m43.)

The one I like the best is where all that needed doing was shortening a pin just a wee bit and substituting a thin plate out of a NEX lens. Then making a screw adjustment to achieve infinity focus.

On my to-do list, for either my m43 or NEX.

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