All actual ALPA lenses in Copal 0 (except Apo-Digitar 5.6/24 mm XL) feature the interlock as standard equipment. Older ALPA lenses can get retrofitted. Please note that only montage by ALPA, by Schneider-Kreuznach or by Linos/Rodenstock is covered by any warranty. In case of self montage the customer/user takes the full risk of damage or malfunction.

Make shure that you have the appropriate screw driver for the montage. We found the usual watchmaker's screwdrivers of not much help in our case: you cannot turn the screwdriver/screws with the right force and feeling.

The 'ALPA Shutter Blade Interlock' comes as one piece with the screws for montage. Please browse first through the whole online manual before starting the montage.

The Copal 0 shutter type features a black lever for opening/closing the shutter blades. It is intended for ground glass work. Opening it with an attached film back and without dark slide would cause a lost image. The 'ALPA Shutter Blade Interlock' blocks the lever securely and still allows a convenient operation of the device.

The black plastic lever for opening/closing the diaphragm on the left side of the shutter must be on the 'closed' (= downward) position = the red dot is covered by this plastic lever = the red dot is not visible in this position.

The black plastic lever for opening/closing the diaphragm on the left side of the shutter must be on the 'closed' (= downward) position = the red dot is covered by this plastic lever = the red dot is not visible in this position.

Remove the two silver coloured screws that hold the X-sync-contact on the shutter (please, keep the whole lens TIGHTLY in your left hand [if you are a right-hander...] and make sure that for this operation the screwdriver is really perfectly fitting into the slots of the screws... - we found the usual watchmaker's screwdrivers of not much help in our case: you cannot turn the screwdriver/screws with the right force and feeling.

If you were successful (without having slipped...) by removing these two screws then you have already succeeded by nearly 50% = you can take away the X-synch-contact-device!

Put away the (also silver coloured) X-sync-contact-device; you will need it again later (the two small silver-coloured original screws are no more needed - they will be replaced by two new, longer and black screws that you will get together with the ALPA 'shutter blade interlock'),

Where the X-sync-contact-device was, you now see a round hole and down in this hole you see a silver coloured rectangular metal 'tongue' which is free on the downwards side and fixed on the upwards side. Please, insert the screwdriver into the hole, move it below the free end of this "tongue" and bend it (the 'tongue') UPWARDS (may be by 0.5 - 1.0 mm = ca. to the level of upper edge of the hole)

Now you put together the 'ALPA Shutter Blade Interlock' with the silver coloured X-sync-contact-deviceand the two black screws. We found it most convenient to prepare the set like this and hold for montage as in the picture shown.

Put the combined 'ALPA Shutter Blade Interlock' and X-sync-contact as in the picture shown (covering the red 'X' - there is only one possible way to place it = no problem!).

Fix it all together to the shutter with the two black screws we will send you together with all the other pieces.

WARNING!: tighten these two black screws SMOOTHLY/LIGHTLY = the threads in the shutter are very delicate!

Fix it all together to the shutter with the two black screws we will send you together with all the other pieces.

WARNING!: tighten these two black screws SMOOTHLY/LIGHTLY = the threads in the shutter are very delicate!

Your lens should now look like this. The lever of the 'ALPA Shutter Blade Interlock' blocks the black lever of the Copal 0 shutter securely.

If you want to open the shutter blades just push the lever of the 'ALPA Shutter Blade Interlock' down and you can open the lens blades as before.

Now you can use the ground glass or live video of your digital back as before.

The 'ALPA Shutter Blade Interlock' snaps in and blocks the lever automatically when you close the shutter blades.

Please make shure that the X-sync is still working. Test it with an appropriate flash. Put the plug of this flash's cable in the X-sync contact of the lens, cock the shutter and fire the the shutter with the flash several times: if it always works (= if the flash fires as perfectly as the shutter) then you are finished - PERFECT!

If the flash (or digital back) doesn't react you might have not bend up or not bend up enougth the 'contact tongue' during installation. If so please start over and correct this with very carefully. Please mind that the screw threads of the Copal 0 shutter are very delicate.