User Guide.

Attaching a lens

1. Remove the cone by undoing the four thumbscrews at its corners. They can be a little fiddly, but you get quick at it. When set up in the field, the flat area on top of the tripod plate makes a handy shelf for the cone and screws.
2. Mount the shutter. With the cone off, mount your Copal/Compur shutter into the hole on the lens board and secure with a lens spanner. One side fits Copal 0, the other Copal 1.
3. Reattach the cone and finger-tighten the four thumbscrews evenly.

Checking focus

1. Set up on a tripod and open the shutter preview lever. On Copal shutters it's the big lever; older Compurs vary — you may need to look yours up.
2. Open the aperture fully and aim at something far away. Several hundred metres minimum, further is better.
3. Snap the ground glass onto the rear standard magnetically. The lens should project an image — upside down and left-right flipped if you're new to view cameras. You get used to it fast.
4. Focus the helicoid. The cones are designed so that infinity requires a small shim, so a distant object won't be sharp right away. Turn the helicoid a touch — it should take under 2mm of movement to reach focus.

Shimming for infinity

You can honestly just start shooting and live with the helicoid not stopping exactly at infinity. But if you want it dialled in, you'll find shims in the spares bag ranging from 0.1mm to 1mm. They fit around the lens mount threading, between the board and the shutter.

With callipers

1. Measure how much helicoid travel it takes to reach infinity focus.
2. Add that thickness in shims between the lens board and the shutter.

Without callipers

• Hold a stack of shims beside the lens and eyeball the gap, or
• Trial-and-error: add shims until infinity lands at the helicoid stop. Tedious, but it works.

Levelling and movements

Point the camera at something closer and more interesting. Once you've framed up, level the camera using the two bubble levels on the rear standard:

• Large level — left-to-right
• Small corner level — fore-to-aft

A geared tripod head helps a lot here.

Rotating back

To switch between landscape and portrait, hold the rear standard firmly and rotate 90° counter-clockwise. The felt in this mechanism is at maximum thickness when new, so it can be a bit stiff — it loosens with use. Magnets help you land on the right angle and resist accidental bumps.

Rise and fall

Turn the titanium knob on the front of the body. Which direction does what becomes second nature quickly. The mechanism is self-locking and allows very fine adjustments.

Lateral shift

1. Undo the locking thumbscrew on the bottom-left of the back.
2. Slide the whole back plate side to side.
3. Re-tighten.

Note: in one shift direction the back can't rotate due to contact between the screw and the rear standard, so get your orientation set before shifting.

A note on bubble levels

The grey levels on the body and ground glass holder can be removed and shimmed. In the spares bag you'll find tiny 3D-printed washers for this purpose. You probably won't need to adjust, but if a level reads slightly off:

1. Unscrew the level.
2. Slip a shim under one side.
3. Re-test.

The best reference is a flat ocean horizon — line it up with one of the ground glass grid lines and adjust the bubble to read level. No ocean handy? A tall vertical structure like an office building works too. Line it up with a vertical grid line, making sure the camera is also level fore-to-aft.

All that said, with film you're at the mercy of straightness in the back, the scanner, the neg holder. Don't lose sleep over sub-degree perfection. Within a degree or two is plenty.

Taking a photo

1. Close the preview lever. Nothing worse than forgetting it's open and accidentally exposing film.
2. Set aperture and shutter speed on the lens, and attach a cable release if you haven't already.
3. Mount the film back. Unlike the original Mamiya mount, this camera uses a sliding mechanism — just slot it in from the side. It should seat securely, and the interlock will allow the dark slide to be removed.
4. Remove the dark slide. These old backs can sometimes leak a bit through the slot, so it doesn't hurt to leave the slide just resting in the slot. Means you won't misplace it either.
5. Cock the shutter and fire. All going well, you've just taken a great photo.

Note: when the back is used off an RB body, you need to flick the little switch below the advance lever to allow advancing between shots.

Using the loupe

Hidden magnets in the ground glass holder attract the magnets on the loupe's base — they mate together reasonably securely, and between shots it makes a nice integral unit.

Diopter adjustment

The loupe ships set up for normal vision, skewed slightly toward short-sightedness. Beneath the lens are five 1mm shims (four plastic, one rubber that contacts the lens).

If you're short-sighted and want to use the loupe without glasses:

1. Remove the top.
2. Carefully take out the lens (gloves help to avoid fingerprints).
3. Move shims from below the lens to above it, always keeping a rubber shim against the lens for tension.

Moving the full stack above gets you to around +0.6 diopters. Beyond that you'll need to wear glasses, which should be fine — the loupe has decent eye relief. You may just need to move your eye slightly to see the full ground glass.

If eye relief is tight, there's an alternate lower-profile top in the spares bag (without the rubber cup) that gives a bigger field of view. Spare spacers and a rubber ring are included in case you drop one.