What would happen if you tried to mount a M lens on a Eos camera?

Started 3 months ago | Questions
Chuck6345 Regular Member • Posts: 142
What would happen if you tried to mount a M lens on a Eos camera?
1

I have a 7d II camera and wonder about using the newer M mount lenses on the camera.

ANSWER:
Canon EOS 7D Mark II
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mcsk Regular Member • Posts: 107
Re: What would happen if you tried to mount a M lens on a Eos camera?

You'd have effectively 26+mm of extension, and a lens stuck at minimum aperture that can't focus. A third party manual focus M lens could work for macro and be super compact, but you'd probably need to make you own adapter.

KiloHotelphoto Contributing Member • Posts: 611
Re: What would happen if you tried to mount a M lens on a Eos camera?

All Canon bodies, M, EF, or RF mount are all EOS.

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OP Chuck6345 Regular Member • Posts: 142
Re: What would happen if you tried to mount a M lens on a Eos camera?
1

I mean 7dII camera which uses EF lenses

Mark B.
Mark B. Forum Pro • Posts: 28,300
Re: What would happen if you tried to mount a M lens on a Eos camera?

Chuck6345 wrote:

I have a 7d II camera and wonder about using the newer M mount lenses on the camera.

Is there even an adapter to do that?

OP Chuck6345 Regular Member • Posts: 142
Re: What would happen if you tried to mount a M lens on a Eos camera?

No adapter that I know about.

Mark B.
Mark B. Forum Pro • Posts: 28,300
Re: What would happen if you tried to mount a M lens on a Eos camera?

Chuck6345 wrote:

No adapter that I know about.

Then that answers your question.  You would need to fabricate a physical mount just to mate it to the camera.  But unless you also know how to pass the electrical communication, there will be no af or aperture control.

There are, however, adapters to mount EF to M.

aglake
aglake Regular Member • Posts: 430
Re: What would happen if you tried to mount a M lens on a Eos camera?
1

Mark B. wrote:

Chuck6345 wrote:

No adapter that I know about.

Then that answers your question. You would need to fabricate a physical mount just to mate it to the camera. But unless you also know how to pass the electrical communication, there will be no AF or aperture control.

The problem is worse than just fabricating a physical adapter.  You'd have to put in optics to account for the difference in where the lens focuses.

A Canon EF-M lens focuses 18mm behind the lens mounting flange.  However, an EOS camera that uses EF (or EF-S) lenses has the sensor 44mm behind the lens flange.  So, unless you include special optics to move the EF-M focus point 26mm farther on, there is no way that an EF-M lens will work on an EF mount camera.

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Mark B.
Mark B. Forum Pro • Posts: 28,300
Re: What would happen if you tried to mount a M lens on a Eos camera?

aglake wrote:

Mark B. wrote:

Chuck6345 wrote:

No adapter that I know about.

Then that answers your question. You would need to fabricate a physical mount just to mate it to the camera. But unless you also know how to pass the electrical communication, there will be no AF or aperture control.

The problem is worse than just fabricating a physical adapter. You'd have to put in optics to account for the difference in where the lens focuses.

A Canon EF-M lens focuses 18mm behind the lens mounting flange. However, an EOS camera that uses EF (or EF-S) lenses has the sensor 44mm behind the lens flange. So, unless you include special optics to move the EF-M focus point 26mm farther on, there is no way that an EF-M lens will work on an EF mount camera.

I figured as much, otherwise Canon would have made an adapter available long ago.

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