| Pax M4 by Yamato|
image by Rick Oleson (Image rights)
The Pax M4 from about 1958 is a revision to the Pax M3 which added a frosted central window to illuminate a bright-line viewfinder frame. The change required Yamato to add a taller top housing. Unlike other Pax models this does not have a dropped shoulder around the rewind, which is a folding crank, replacing the rewind knob of earlier models. The film speed reminder dial also differs from that of the M3, and the name Pax is not impressed in the leatherette of the back, as on all the previous Pax cameras. The lens is a Luminor Anastigmat f/2.8 45mm.
The rangefinder adjustment screws are also differently placed. The screw to adjust for distance (at infinity focus) is inside the camera; it is accessed through a hole at the top of the internal panelling behind the lens. The screw for vertical alignment is accessed by removing the front screw of the three that secure the flash shoe; the adjustment screw is beneath that screw hole.
The camera was also sold as the Pal M4, Rex, Rex M4 and the Tac Deluxe .
| "Rex M4" version|
image by Kate Andrews (Image rights)