• Mamiya 7II Brochure
• Mamiya 7II Instructions

The Mamiya 7II uses one 6V battery. From the manual:
The Mamiya 7II uses one of:

• 4SR44 silver oxide battery
• 4LR44 alkaline battery
• 2CR1/3 lithium battery

Source: http://www.photoethnography.com/ClassicCameras/batteries.html
Also known as: PX28L, 2CR1/3N, L544, L544BP, V28PXL, K28L, 2CR11108, 2CR1/3H, CR28L, 1406LC

Size: 13.0mm D x 25.2mm H

6V 160mAh Lithium

This is the same size as the PX28S / 4SR44 but because it is lithium, it is 6V instead of 6.2V. Most cameras will not mind. The lithium performs better in cold-weather conditions than the silver-oxide. Lithium cells have a shelf-life of about 10 years unused.

Note that it's often cheaper to use two stacked CR1/3N batteries instead of a single PX28L.

Source: http://photo.net/medium-format-photography-forum/00AsL3

Matt Hill of Mamiya America Corp. posted this at http://www.macuserforums.com/webx?13@50.ppcXawYKoNP.4@.ee72afa/7

• 43mm f/4.5: front nodal point = 22.0 mm; rear nodal point = 18.2 mm
• 65mm f/4: front nodal point = 29.0 mm; rear nodal point = 8.1 mm
• 80mm f/4: front nodal point = 26.0; rear nodal point = 25.3
• 50mm f/4.5: front nodal point = 24.8mm; rear nodal point = 26.2mm
• 150mm f/4.5: front nodal point = 22.8mm; rear nodal point = 65.9mm
• 210mm f/8: front nodal point = 94.2mm; rear nodal point = 134.1mm

The technical reference points they supply are that the front nodal point reference is from behind the first lens vertex and the rear nodal point is that distance in front of the last lens vertex (toward the front of the lens).

I measured the entrance pupil (the no-parallax point) for the 80mm lens at around 28mm from the front (filter thread) of the lens.

Scanning with 3200 PPI (Reflecta MF 5000), printing at 300 DPI. Note, the scanner cannot resolve 3200 PPI, but according to some 3050 DPI.

In theory:

• Actual image size of the negative: 56 x 69.5mm
• 3200 DPI = 1260 px/cm
• 300 DPI = 118 px/cm
• Height: 5.6cm x 1260px = 7056 pixels
• Width: 6.95cm x 1260px = 8757 pixels
• 7056 x 8757 = 61,789,392 pixels = 61MP
• Printed at 300 DPI:
  • 7056/118=60cm
  • 8757/118=74cm