Contax 645 w/ DB: 35/3.5 vs. 45/2.8?

[carstenw]

I have one question though: when half-pressing the shutter, it focuses. The button on the rear which I thought would be one-shot focus doesn't do anything, but I probably have to set that up somehow. The question is this though: the first time I half-press the shutter after powering up the body, the motor just spins and does nothing. After that it works fine. Is that normal?

I figured out the one-shot focus button: I must set it to M first.

On second listen, the motor sound might actually be in the film back...

I can't reproduce the behaviour where the first attempt to focus will fail any more. Perhaps I was doing something wrong. Now it appears to work every time, with the dark slide in or out. Hmm.