Contax II slow speed curtains respond?

[pb908]

I just realized that my Contax II have "Weird" curtain respond when set on slow speed.

normally, I'd expect to hear/see that the first curtain drop (fast), then delay (as well as the clockwork noise come when delay mechanism work), and then the 2nd curtain drops.

but what I get is:
1. 1st curtain drop slowly (not very slow), and I can hear the clockwork noise as well.
2. Then a small delay, the clockwork noise is still can be hear.
3. Then 2nd curtain drops fast.

sometimes, the 2nd curtain drops as slow as 1st curtain, at that time the 2nd curtain was slow, I can hear the clockwork noise as well. But most of the time, the sequence happen as I describe above.
Slow 1st curtain, delay, and fast 2nd curtain.

I didn't get this respond when I set somewhere around 1/25s and above. So I can say that at high speed shutter, all curtain drops at the same speed.
If there is the culprit, it must be something related with the delay mechanism, but I haved't got a time to inspect it nor to learn how it work. Any idea/helps guys?

 

[Highway 61]

The 1st curtain bottom drum main spring is unhooked or broken.

 

[pb908]

Thanks Highway61. in fact when I check the shutter this morning, the 1st curtain spring is still attached there, not unhooked or broken.

correct me if I'm wrong.
as far as I know, when normal speed selected, after I press the shutter, the 1st curtain is released from the hook and drops, along with the movement of shutter tape (of 2nd curtain) going down. (during that time, 2nd curtain start to unrolls and then drops to create the slit width). at this time, the 1'st curtain actually free to drop (pulled by it's spring), but because of restriction with the shutter tape, it drop at the same speed as the tape (and 2nd curtain), which makes the slit width constant, the speed of the slit drops is mainly determine from the 2nd curtain spring.
am I right ?

what I see here is that during slow speed selected, there are gears (which connect to clockwork delay ?) that slows down the movement of the 2nd'curtain tape just after I press the shutter.. this way, 1'st curtain (which is free, but stick to the 2nd curtain tapes by restriction), is drops slowly.
at the end of the cycle, the delay gear is freed from delay mechanism and 2nd curtain drops at faster speed.
is that correct ?

at 0.5s speed, I can see clearly the differences of speed between the 2 curtains. how about yours ?

 

[Highway 61]

The first curtain is totally passive, has no connection with the slow speeds delay mechanism and so, always must run at the same speed because it's driven by its bottom roller drum spring only.

On these cameras, when the first curtain runs slowly, it's often because of a problem with the bottom roller drum spring. This is a very complex spring, actually there is a set of three springs in the drum, and you can't know if it's OK or unhooked/broken unless you strip it down fully.

Here is a sketch from Rick Oleson so that you get what I'm speaking of.

Other serious option is that you have got one ribbon snapped (broken), it may very well lead to the same results, because with a broken ribbon there is no tension left at all for the matching side spring in the bottom roller drum.

 

[rockisshell]

The Contax II, introduced in 1936 by Zeiss Ikon in Dresden, was the first camera combined with an offer and viewfinder but its virtues went much further than that.

 

[batterytypehah!]

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