These are the instructions for the new "Auto-Aperture simulation" Leitax mount for Leica-R lenses on Pentax cameras.

This is what you receive from Leitax

To remove the original Leica-R mount, please follow the instructions for your Leica-R lens model at the left side of my Leica-Pentax page.

Now put your lens on the table like in the picture, with its lever at the left side.
If the lens has oil at the place where we are going to install the Leitax black ring, then this ring will not return freely like you can see at the movie below.
In this case we have to remove the aperture ring...
...and clean that oil and grease from this edge of the lens, the top and the side, I use a kitchen paper.
Also clean the superior part of the internal side of the aperture ring.

Then you can put the aperture ring in its place.

And now you can install the black ring.

Pay attention at the relative positions of the levers of the lens and the black ring

Now you can install the Leitax mount.

The cut-out of the mount allows the lever to move freely.

Make the holes coincide. Here you have to pay attention not to move the small ball from its place when installing the Leitax mount.

You can put the screws, but not tighten them completely yet.

The Leitax mount for Pentax has 5 holes instead of 6. This is because camera's mount  locking pin would get inserted into the 6th. hole.

Check if this lever of the black ring can be moved freely and it returns with the force of the lens iris spring.
If all is correct you can tighten the screws.

Ready, the Pentax camera now has a Leica-R lens with almost Auto-Aperture.

This is how I use it:
I preset the desired aperture on the diaphragm ring of the lens.
Then, I can frame and focus with precision pushing
down the lever of the Leitax mount, which opens the iris.
When the subject is in focus, just releasing the lever will put the iris at the preset value, and I can take the picture without having separated my eye from the viewfinder in all that time.

Here you can see how the Leitax mount lever can actuate the iris of the Leica-R lenses.

And here you can see our first feedback from a customer of the new auto-aperture simulation Leitax mount.

For any question, please write to

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