Well, I tried the Zeiss on the weekend, with mixed success. At least it seems to work, the shutter speeds seem OK.
A few things I've learnt, for anyone planning to use one of these old cameras:
1. Remember to wind the film on between exposures.
2. REMEMBER TO WIND THE FILM ON BETWEEN EXPOSURES!
3. Focussing is extremely hit and miss, you just rotate the lens to the correct distance marking (min 2 metres) and hope. I see now why so many of my father's photos seemed blurred!
4. The shutter is so quiet when it fires, I first thought I hadn't cocked it, and did it again (double exposure #1!). The second time I pressed the shutter button it made a faint click, and I realised it had fired first time too.
5. Depth of field in not great, the lens is 105mm focal length, which by my calculations is about the equivalent of a 28mm on 35mm film, or 18mm on my D300 (so it's quite wide). I would have expected the depth of field to be a bit better at f8.
6. I used my D300 as a light meter, I set the ISO to 100 (LO-1) and set the aperture to match what I set the Zeiss to, and set the Zeiss shutter speed to match the D300. The Exposures seem slightly over-exposed, so maybe the shutter is dragging slightly.
7. For a camera that takes such a large negative (6x9cm) the camera itself is very small. Folded it will fit in a large pocket, and I found it very light to hold, which made holding it still at less than 1/60 sec more difficult. I was holding with both hands on the body (the shutter button is on the left), and it felt odd not holding the lens to stabilise the camera. I guess I'm used to the size and weight of the D300.
Anyway, at the end of the exercise, the camera still works, and I will shoot a roll of film at Christmas time, in memory of my father. I may try to get black and white film for this exercise.
Anyone have any more tips (specially about focussing and framing)?