Valid instructions for:
AE Planar 50/1.7
AE Sonnar 85/2.8 (only Japanese version with holes at the mount base)
This is the AE Sonnar 85/2.8, note the white 22 number on the diaphragm ring.
First, unscrew the four screws from the mount base.
Now, lift the diaphragm ring and bayonet all together.
Pull apart the diaphragm ring from the bayonet, watch for the bearing ball.
Face the ring actuator to the lens counterpart.
Make them coincide and put the ring on its place in the lens.
Take the included spring and put the elongated shape end in the ring's shaft, making the spring body go downwards.
If necessary, help yourself with the plastic tool.
The included knitting needle will help us to put the other end on place.
This is how we can easily put the other end on its place with the needle's help, pay attention to the correct spring position ( spring body outside), so it will stay in place.
Spring in place.
With the spring in place you can open and close the diaphragm when rotating the ring.
Now, put some special grease in the small spring hole.
And bring the small ball to it.
Ball in its place.
This is correct position of the steel ring.
The steel ring is in place, now make sure the small ball coincides with one of the detents like in the picture, you may have to rotate the diaphragm ring.
So we can install the new bayonet, the red dot goes in front the scale center of the lens.
Go down making the screw holes coincide. You must feel the small spring pushing up when you press the bayonet against the lens.
Put the four screws and you are done.
Time to enjoy the Zeiss lens with our Pentax camera.
To buy the replacement bayonet, please go to Leitax Homepage