Argus C4/C4R - Holding Camera for Changing Lenses

The
easiest method to interchange lenses on your Argus C-4 Camera is as
follows: Hold C-4 camera in the palm of either hand (with front of
camera facing you) so that your thumb is on top of C-4 rangefinder
wheel. Your index finger should be on back of camera, while your other
three fingers grip base of camera. The purpose of holding your camera
in this position is to allow you a firm grip on the camera and at the
same time enable your thumb to turn or hold the rangefinder wheel,
wherever required in the following instructions.

Your
rangefinder is a precision instrument. Whenever any lens is removed
from the camera, be careful to avoid turning the rangefinder dial. To
avoid damaging the rangefinder, NEVER turn dial more than 4 teeth
beyond 3 foot mark or 4 teeth beyond infinity (oo) mark. In other
words, NEVER turn rangefinder so that the index mark on the body is
pointing to any area in the illustrated 'DANGER ZONE'.