Just finished a frame counter for my Leicina, as I'm going to need it for a project I have in mind - thought some might be interested.
Well you might ask, why do you need one, and whats wrong with the 2 counters on the side of the camera? They're OK but not very accurate, and you have to keep an eye on them to know where you are. They don't actually tell you where you are exactly in the roll. And they are only good if you can see them! What happens if you want to operate the camera remotely?
I used this sweet little module from RS components:
It runs off a lithium coin cell for 3-4 years so it can be removed from the camera and remember what the frame count was.
Here are a couple of pics:
The big black button on the top is a remote run button, the small button to the left of the display is the reset button.
I used a connector on the case so I can add extension cables, and there will be another connector eventually for external trigger input, and maybe a frquency meter!
The ugly yellow blob on top of the camera is a home made connector (din plug pins epoxied into some strip board) that works OK
This could easily be made for any camera that has a flash output, should you need one!
It works perfectly on the Leicina up to 25fps, but not on the 54fps- I suspect the contacts in the camera don't have time to close properly at that speed.