12-17-2018 02:27 PM
12-17-2018 03:35 PM - edited 12-17-2018 03:54 PM
The camera doesn't know that a lens is attached when you use a simple adapter for M42 lenses.
First, make sure the camera in not in the green "A" mode. Then look in the camera menu for Custom Functions and under CF II there will be an option for shutter release when no lens is attached.