bgsquare
Subscriber
If you move the helical to closest focus- longest extension- the 3-1/2' tick mark should be just a bit past the center mark. the manual says the tick mark should be at the red infrared mark. And then you can test other distances. Distant target for infinity.. The manual says to set distance scale, rangefinder, and film plane focus all to 15 feet. But you can use other distances, assuming that film plane focus and rangefinder focus are in agreement (not likely but we'll let that slide for now...). But the starting point is the closest focus and the scale.
Depth of field is not an absolute value. For example, the Rolleiflex manuals say use the scale for a certain level of enlargement but use one aperture larger (smaller DOF) for greater enlargement. Circle of confusion, print viewing distance, on and on. But as a rough working idea, the scale on the Medalist is fine.
Thank you Dan!
