I just got a Teleskop 1.7x auxiliary lens for my Zeiss Contaflex 1. There are no instructions, so I have a question: is any exposure compensation needed when this lens is fitted or does it work at the normal f2.8?
No, no exposure compensation is needed. I've shot with this in the past, and the photos were very good. I was shooting in daylight with a ISO 200 film, so I was shooting at f/8 and smaller.
You have the bracket that slides onto the front of the camera, right? That bracket also holds the stereo device.