Canon EF lens mount mechanical specifications

Are there any mechanical specifications for the Canon EF lens mount? Or is
this something that third parties have to reverse engineer?

My immediate need is to know the angle between the red dot index mark on
the mount and the top of the lens when the lens is locked in place.

I make adapters to upgrade microscopes and medical instruments for digital
cameras. See:

http://www.truetex.com/micad.htm

I have my own CAD 3D model of the lens bayonet, but this is based on my
reverse engineering of third-party EOS to T-mount adapters:

http://www.truetex.com/topcon-fundus.dwf
[require this free viewer:]
http://usa.autodesk.com/adsk/servlet...112&id=4424149

"Richard J Kinch" wrote in message
.. .
Are there any mechanical specifications for the Canon EF lens mount? Or
is
this something that third parties have to reverse engineer?

My immediate need is to know the angle between the red dot index mark on
the mount and the top of the lens when the lens is locked in place.

I make adapters to upgrade microscopes and medical instruments for digital
cameras. See:

http://www.truetex.com/micad.htm

I have my own CAD 3D model of the lens bayonet, but this is based on my
reverse engineering of third-party EOS to T-mount adapters:

http://www.truetex.com/topcon-fundus.dwf
[require this free viewer:]
http://usa.autodesk.com/adsk/servlet...112&id=4424149

Your best bet would be to contact Canon themselves. You probably would have
to pay a licensing fee to get the specifications from them. Some 3rd party
lens makers, like Sigma, don't get this information and the lens has
electronic compatability issues with newer caneras where the lens must be
sent back to Sigma to be rechipped. Since you don't have this issue, it may
be better for you to reverse engineer for your data.
John

JohnR66 wrote:

"Richard J Kinch" wrote in message
.. .
Are there any mechanical specifications for the Canon EF lens mount? Or
is
this something that third parties have to reverse engineer?

My immediate need is to know the angle between the red dot index mark on
the mount and the top of the lens when the lens is locked in place.

I make adapters to upgrade microscopes and medical instruments for digital
cameras. See:

http://www.truetex.com/micad.htm

I have my own CAD 3D model of the lens bayonet, but this is based on my
reverse engineering of third-party EOS to T-mount adapters:

http://www.truetex.com/topcon-fundus.dwf
[require this free viewer:]
http://usa.autodesk.com/adsk/servlet...112&id=4424149

Your best bet would be to contact Canon themselves. You probably would have
to pay a licensing fee to get the specifications from them. Some 3rd party
lens makers, like Sigma, don't get this information and the lens has
electronic compatability issues with newer caneras where the lens must be
sent back to Sigma to be rechipped. Since you don't have this issue, it may
be better for you to reverse engineer for your data.
John

It looks like all "Richard J Kinch" needs to make is a purely
mechanical adapter.
The reverse engineering of a lens should suffice, as some people use a
lenscap as a pinhole lens (after boring a hole in it) on a Canon DSLR
and seem to get a reasonable result.