Mamiya RB76 Pro SD - shutter and dark slide issue

I am still learning how to use my RB67 but am confused as to why I can press the shutter when the dark slide is in place. When there is no film in the camera I cannot press the shutter when the dark slide is in place.

However when I load film - either into a manual film back or an auto film back I can press the shutter and continue to do so with the dark slide inserted. It is not the multiple exposure lever.

Any thoughts please.

You're either not pushing the dark slide far enough in to engage the shutter release lock, or the pin on the slide is missing / bent so it will not engage the lock. There should be 4 metal pins on the handle end of the dark slide that push into the film back when firmly in place. One of those pins engages the shutter lock. If the pin is missing or bent out of shape, it will not engage the lock.

One of those pins engages the shutter lock. If the pin is missing or bent out of shape, it will not engage the lock.[/QUOTE

WOW.. that was real quick you from down under Tasmania "sparky"... I have a few film backs.. and all the dark slides do have the 4 metal pieces sticking out... but it appears the top one on the rotating back piece does not get pushed in unless I twist the dark slide slightly - I guess that is what you are talking about. I might need to look at adjusting the piece in the rotating back.

Thank you very much

The beauty of a fully mechanical Camera - what a wonderful piece of equipment!! Got is sussed now thanks again.