Contax IIa Frame Spacing

[KoNickon]

OK, I'm back again, and now the topic is a IIa I've had but used only rarely, mainly because the shutter was tapering at the top speeds. I think I've fixed that for the time being (adjustment screw hidden below the shutter) and was anxious to try it out today.

All went well on that score, but I only got 19 shots on a roll of 24. In examining the negatives I found there was very wide spacing between almost all the frames, like 5mm. What gives? I thought 35mm cameras wound film based on the sprocket gearing, so frame spacing should be pretty consistent, and much tighter. I did what I always do when film is loaded -- turning the rewind knob to take up slack in the cassette. I think I've had this problem with my other IIa also.

Thanks in advance for your thoughts.

 

[sevo]

All Contaxes and Kievs are a bit vulnerable to excessive spacing - indeed most cameras with a knob wind mechanism (or early single/dual stroke lever wind gears) are. As the cameras age, the grease in the retaining mechanism gums up - once they are in that condition and you don't wind them in one go, the ratchet may slip back a few teeth at each partial turn of the wind knob, so that the film is wound on some more than the shutter and counter mechanisms. A cleaning will fix it...

 

[KoNickon]

Thanks for this. I'll try to wind in one twist if possible. No question that the camera needs a cleaning, though, so that is the ultimate answer.

 

[Highway 61]

All Contaxes and Kievs are a bit vulnerable to excessive spacing - indeed most cameras with a knob wind mechanism (or early single/dual stroke lever wind gears) are. As the cameras age, the grease in the retaining mechanism gums up - once they are in that condition and you don't wind them in one go, the ratchet may slip back a few teeth at each partial turn of the wind knob, so that the film is wound on some more than the shutter and counter mechanisms. A cleaning will fix it...

Yes but while the Kievs are famous for this, due to how their advance mechanism is build, allowing zero machining tolerance unless frame spacing will be uneven, the postwar Contax IIa is built totally differently and the advance mechanism is directly driven by an independant geartrain. It's very rare to get uneven frames spacing on a Contax IIa or IIIa and I'd rather think of something loose than of something dirty.

 

[KoNickon]

What might be loose? I realize that's almost unfair to ask, but I don't detect anything loose so I'd appreciate being pointed in the right direction. Thanks.

 

[Highway 61]

Check the fork which drives the take-up spool. There must be no play at all between that fork, the film advance teethed capstan, and the winding knob. Actually everything's here relies on a small geared cylindrical wheel which is hidden between the upper shutter module and the camera main chassis. I do hope that nobody dismantled your camera then reassembled it forgetting to fit that small but important part back in place.

 

[sevo]

And check that the take-up spool fork is friction coupled to the sprockets, with not too much torque - if that coupling binds, the film will be pulled across the sprockets.