Welcome to our Zeiss/Contax section. As you know, this site is focused to give more possibilities to our Pentax film or digital cameras and, finally, with our replacement bayonet, we can use a selection of lenses for Contax, made by Carl Zeiss.

The same as with Leica lenses, this conversion is fully reversible and will not damage the lens nor the camera. The Zeiss/Contax lenses will focus to infinite, our cameras will give focus confirmation, will meter in Av mode (stop  down), and the modern Pentax cameras will stabilize all of them.

Unfortunately, the Contax lenses present a variety of different bayonets models and sizes, and the gradation of difficulty goes from easy to almost impossible. So lets start with the easy ones, the Contax MM type with small diameter bayonet.

Please scroll down for the instructions

Super Program Contax
As far as I know, this is the complete list of Contax MM type prime lenses with narrow mount that we can use.

MM lenses can be easily recognized as the smallest aperture on the scale is green.

MM Distagon*   18mm   F4
MM Distagon*   21mm   F2.8
MM Distagon*   25mm   F2.8
MM Distagon   28mm   F2.0
MM Distagon*   28mm   F2.8
MM Distagon*   35mm   F2.8
MM Planar*   50mm   F1.7
MM Planar*   50mm   F1.4
MM Sonnar*    85mm   F2.8
MM Sonnar* 100mm   F3.5
MM Sonnar* 135mm   F2.8
MM Tele- Tessar 200mm   F4

The lenses marked with an asterisk * have been already tested.

Available a special bayonet  for  two  AE lenses:                                      

AE Planar*   50mm   F1.7
AE Sonnar* (Japan)   85mm   F2.8

The instructions for the two AE lenses are  HERE

- Our customer and friend Lazare Caspi from  www.monuniverspentax.com has found a simple way to use the Vario-Sonnar 3,5-4,5/28-70 on Pentax cameras, please take a look here.

- I've tried the Vario-Sonnar 3,4/35-70 , which is said to be as good as primes, and this is the way to use it in Pentax. Warning:  this one is a bit risky, I would recommend only for professionals and really daring and advanced diyers. Take a look here.

- I can offer now a special mount for the pancake lens Contax Tessar 45/2.8 , MM type only. Look here

- Our client and friend Laurent managed to install our Contax mount on his Vario-Sonnar 28-85
NEW! Conversion instructions for the Vario-Sonnar 80-200/4

Bayonet and tools sales at the
Leitax Homepage

- Due to strict security, the postal service to the US can take several weeks, US customers please consider the UPS option.


 MM lenses with narrow mount instructions :

All the MM lenses tested are identical inside, so the following instructions will work for all of them, and I am pretty sure, for all the rest.

distangon 35 These instructions are for the MM lenses only.

This is the Carl Zeiss MM Distagon 35mm F2.8
back First, I would take a picture of the bayonet, so it will be easy to rebuild later
special Some lenses have this curved piece here, we have to remove it. This one is the Sonnar 135mm.
unscrew Now, unscrew the three upper bayonet screws. Use a good screwdriver, not those cheap ones from hobby shops, these screws are glued to the threads and it is necessary to make enough pressure and turn them carefully.
remove And remove it.
bayonet Now, unscrew the bayonet.
lift And lift the diaphragm ring together with the bayonet.

Have the aperture ring in a middle position before lifting it, and lift it vertically without twisting it while lifting it, to avoid moving to the extreme side the internal iris mechanism, which could be difficult to put again in its place.
cover Ok, it's better to cover the lens meanwhile we are working on the ring.
separate Now, we have to put the bayonet apart from the ring.
apart When they are apart, look for the bearing ball, it should be near its place, over the small spring.
molla Now look at this spring, we need to uncouple this side from the hook.
Usually, there is a bit of glue to secure it, don't pull the spring, it can be deformed or broken, just scratch patiently the glue with a pointed tool or a needle.
free The spring is free now.
plastic tool With the plastic tool, lift a bit the steel ring.
push And push it to the right, so it can be removed from the Contax bayonet.
unscrew In case the steel ring doesn't move to the right, it means it got glued just under the square slot. This is because they dropped glue over that screw and some glue went under the steel ring. Also could be glued around the round holes, from the bayonet screws.
So we need to remove that screw and the square piece that it attaches .
liberate Now, to unglue the steel ring, use the plastic tool to avoid scratches. Put it like the picture and turn it.
Please don't try to remove the steel ring lifting it by the opposite side, you will bend it.
ring Put the diaphragm ring on the lens, you will see a lever inside that commands the blades, which goes inside this u shaped piece of clear metal.
Now you must be able to open and close the diaphragm rotating the ring.
grease Put a little bit of the special grease on this small spring, so the bearing ball will get sticked to it.
bring Bring the small ball to its place , better don't use tweezers , the tip of your screwdriver with some special grease will not lose it,
ball And the ball on the spring, leave an small amount of grease on the ball.
steel ring Now it's time to put the steel ring, notice the hook goes downwards.
square And this square slot goes here.
adjust Turn slightly the diaphragm ring so the small ball will coincide with one of oval shaped holes.
view Another view of the small ball and the steel ring on it.
correct Here you can see all is in correct position, the small ball, the round hole for the screw and the square slot.
rest And the rest of holes too.
bayonet So we can install the new Pentax bayonet, be careful now, first find the correct position looking at the red dot, it goes in front the lens scale center. Then check if the screw holes are well aligned, and finally put the Pentax bayonet lowering it vertically.
screwing You should feel the spring pushing back when you press the bayonet against the lens, in this case you can screw the bayonet and the work is finished.
self portrait So we can use several Zeiss/ Contax lenses on our Pentax cameras, these lenses are on par with Leica and the best Pentax Limited .

To buy the replacement bayonet, please go to Leitax Homepage
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