Pentax Multi Mount: Extend the Range of Lenses Available for Pentax Camera

Hat Tip: Imaging Resource via Pop Photo

The Pentax K+ Multi Mount (PK+MM) is designed to replace the original mounting ring in Pentax cameras, allowing the camera to utilize non-Pentax mount lenses.

 Using the mount does require removing the original mount first. This is a fairly simple operation performed by removing a few screws, but does pose a slight amount of risk.  Replacing the mount will result in the mirror/sensor area of the camera being exposed to the environment (similar to replacing the lens).  Make sure to replace the mount in a dust-free environment to prevent contamination of the camera's interior.

Care should also be taken when handling the screws.  Stripping the screws heads is fairly easy to do.  This makes mount replacements more difficult in the future.  The screws are also easy to lose.  Try handling the camera over a table or container with raised edges to catch any dropped screws.  (A large, shallow plastic tub works for this.)

Replacing the mount instead of using an adapter ring does have an advantage: no image degradation.  The Adaptist website has some sample images taken with lenses mounted with the replacement mount.  The results shown are fairly impressive.  (You do have to wonder how many pictures didn't make the gallery.)


Limitations

The replacement mount isn't perfect.

First, it can't be used with all Pentax cameras.  The excluded cameras are primarily the weather-resistant models.  A replacement mount for the weather-resistant models is in development.

The mounted lenses can only be controlled manually.  No auto-focus or automatic aperture control.  There is also no release catch.  The lens is kept in place using a tension spring.

There are also additional steps necessary depending on the type of lens being mounted.  The most intrusive being the permanent modification to the aperture lever of C/Y lenses.

You also need to ensure that the end element of the lens clears the camera's mirror.

Limitations aside, the mount's expansion of lenses available when using Pentax cameras could prove useful to Pentax users.  Especially those with a wide variety of camera equipment at their disposal.