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How to Build a 4×5" Pinhole Camera

Easy Step-by-step Instructions


This camera is an inexpensive way to get into large format photography. The negatives are big enough to print lovely silver gelatin contact prints, and can be used for alternative printing processes like cyanotype, van dyke, and kallitype. The following list includes everything needed for construction except for the film. The costs are based on prices in St. Paul, Minnesota, USA in August, 2005.

 

Materials

  • #2 Xacto knife – 5.49
  • extra blades – 2.49
  • aluminum or steel straight edge (1 meter long) – 6.99
  • 1 sheet black on black foam board – 4.99
  • 1 sheet black on black matt board – 4.99
  • wood glue or Elmers-type white glue – 1.99
  • 49-52 mm step up ring – 7.99
  • 52 mm lens cap – 5.99
  • 2 ea – 2 inch X 4 inch Velcro hook and pile with adhesive – 3.59
  • 12 inches of 1″ wide Velcro hook and pile with adhesive – 6.97
  • pine molding, 1″ wide X 10” long – found in the garage
  • black plastic 35 mm slide mounts – 20 ea for 3.95
  • Total for above items: $55.43
  • pinhole (hobby drill hole in drink can aluminum or brass shim stock)
  • 4X5 inch sheet film holders (used)

I bought the film holders for $8 each at a used camera store. They can be purchased on Ebay as well. These instructions require a 4X5 inch film holder for each step in the process. The same instructions could be followed to make a camera for other film holder sizes. I made a camera to match an old wooden 8X10 inch film holder that I bought on Ebay using the methods as outlined here. The camera illustrated here is a 75 mm focal length, which is a relatively wide angle for 4X5 film (‘normal’ focal length is about 150 mm).

Construct the camera back

This is the most important piece of the camera, so measure carefully. The back, bottom, and sides of the camera will be constructed using a film holder for dimensions, and to help line up the pieces during the gluing process. Cut a piece of matte board to fit in the slot above the light-trap ridge on the film holder. This piece will measure slightly less than .75″ (19.05 mm) by the width of the film holder – 4.765″ (121 mm). Cut another piece the same width of the film holder. Cut the length so the matte board rests on the flat just below the light-trap ridge, and is even with the bottom of the film holder. Tape these pieces to the film holder with loops of masking tape.

Cut a piece of foam core to exactly the same width as the film holder. Spread wood glue over the surface of both pieces of matte board. Line up the sides of the foam core piece to the sides of the matt board and clamp or weight it down until the glue sets (about 10 minutes).

Remove the glued camera back from the film holder, and trim the top and the bottom of the foam core to match the matt board. Put a new blade into the X-acto knife. Carefully cut the image hole from the matt board side. Keep the knife vertical and make the cuts as clean as possible. Congratulations! The most difficult part is done.

Glue on the bottom of the camera

Cut a piece of foam core to the same width as the film holder. Set up a means to clamp the bottom of the camera to the camera back (see photo).

Apply wood glue to the bottom edge of the camera back. Place the film holder flat on a table, and place the camera back on top of it, with the slot lined up with the light-trap ridge. Align the camera bottom piece to the glued edge of the back, with the edge of the bottom flat against the table, even with the back of the film holder. Clamp in place for 10 minutes, or until the glue sets. Trim the camera bottom to the correct length for the pinhole to film distance that you require. The film plane will be approximately 5 mm behind the surface of the matt board that faces the film holder. On this 75 mm focal length camera, the length of the bottom piece is 83 mm.

Glue on the camera sides

Cut the left and right sides of the camera from foam core. The sides will be flush with the bottom of the camera, and even with the top of the back. On this camera the side dimensions are 83 mm X 165 mm.


Construct the front of the camera

Cut the foam core even with the outside edges of the sides and bottom. Find the center of the opening in the film holder. Carefully mark and cut a hole in the foam core at this location. The hole here is 1.5” in diameter (about 38 mm). This camera includes a slot to hold a black plastic slide mount, so the pinhole can be changed.

Glue the front of the camera to the sides and bottom. Install the pinhole.

Finishing the camera

Cut a piece of foam core to match the sides and front of the camera. The back of the top will butt against the front of the film holder. Glue and clamp the top. The picture at the top of this article shows the fit of the camera top.

Epoxy a step-up ring for filters and lens cap to the front of the camera. 52 mm seems to give the best choices of used filters. Install the lens cap.

This camera is attached to the tripod by 2” X 4” pieces of Velcro on the bottom and one side of the camera. The film holder is held against the back by Velcro strips attached to 1″ pine molding strips.