[Leica] A Heliar-M lens conversion

[Jeff S <4season@boulder.net>]

I just took delivery of my new 15mm Voightlander Heliar lens on Saturday
and for convenience's sake, decided to turn it into a full-time M lens
by cementing a Leica M adaptor to it.

Okay, now that you've all stopped gagging, here's the trick to doing it
right:

Degrease the face of the M adaptor where it contacts the lens with your
favorite cleaner (I use acetone). We'll leave the lens and all threaded
surfaces alone.

Very sparingly apply a little Pliobond cement to the face and allow it
to dry 'till it's no longer tacky. Don't apply cement to the threads or
any part of the lens.

Screw the adaptor onto the lens and tighten down firmly. I use a fat
rubber band to get a grip on the bayonet, and grasp the lens by the
depth of field ring. For safety's sake, we'll set the focus and aperture
rings to their center positions and take care not to torque them past
their stops.

Results are great: The "Heliar-M" works just like any other M lens but
if need be, you can still remove the M adaptor--with some effort.
Because we didn't get cement onto the threads, once it breaks free, the
adaptor spins off easily. For safety's sake, let's not use our M cameras
as wrenches.

Observation: I wasn't crazy about Cosina's M adaptor because in normal
use it's designed to be mounted and unmounted with the aid of a spanner
wrench, whereas Leica's part can be removed by hand pretty readily. But
in this particular application, that becomes a non-issue, and the Cosina
part is cheaper. I got the genuine Leica part because that's all that
was in stock. It's nice. It's also $100+ if you have to buy it new.

Future project: I'm thinking along the lines of an M rear lenscap with
tiny Velcro'd pouch affixed for keeping the lens + finder together and
properly protected but very handy.
- -- 

Jeff Segawa
Somewhere in Boulder, Colorado