shutter curtains, and the light seals that almost always need replacing. Expect to spend an evening on your first body and about forty minutes on the fifth.
Chapter 4: Reading a Rangefinder
A coupled rangefinder is the most rewarding mechanism on the bench and the one people avoid the longest. In this chapter we walk through the vertical and horizontal alignment screws on a Canonet QL17, how to judge the patch against a rooftop at 90 metres, and why you should never chase focus at the near limit first. Two shims and a steady hand fix roughly eight out of ten bodies that arrive described as "focus is off".
Chapter 5: Cleaning Without Damage
Solvents are where beginners do real harm. This chapter covers what belongs on a cotton swab and what never does, how to lift haze from a rear element without touching the coating, and the case for leaving light fungus alone when the glass is otherwise sharp. There is a short section on ultrasonic baths and the four parts that must never go in one.
Chapter 6: Testing and Calibration
A camera is not finished until it has been measured. Here you will build a five-dollar shutter tester from a photodiode and a phone microphone, log the actual speeds against the marked ones, and learn the tolerance that working photographers accept in practice — roughly a third of a stop at 1/125 and considerably looser at 1/1000. We also cover the film test roll that catches everything the bench missed.
Closing notes
Repair work rewards patience over talent. The first body you open will take three sittings and you will lose a screw into the carpet; the tenth will take an afternoon and come out better than it left the factory. Work slowly, photograph every step before you take it apart, and keep the parts of anything you cannot save — the drawer of donor pieces is what makes the next repair possible.