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The Pin Hole Camera
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Earliest Camera style.
Light tight box.
Pin hole to project the image.
The image forms on the back of the box
(opposite the pin hole) where it can be
observed and/or captured.
The Pin Hole Camera
Pin Hole
Subject
Camera
Image
The Image quality is determined by:
• The quality of the pin hole (roundness).
• The thickness of the material that the pin
hole is in.
• The diameter of the pin hole.
The Pin Hole Camera
•
The optimum diameter of the pin hole is approximately given by the
equation:
Where
d is the pinhole diameter
f is the focal length (distance from pinhole to image plane)
λ is the wave length of light, 550 nm (yellow-green)
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The material that has the pin hole should be as thin as possible.
The Pin Hole Camera
• Recall that the equation for the Aperture
size is given by
• F= Focal Length / Diameter of the Aperture
• F =f/d
Where: F is the focal ratio
f is the focal length … the distance from the pin hole to the film/sensor
d is the diameter of the aperture
The Pin Hole Camera
Transforming your DSLR camera
into a pin hole camera
Pin Hole Camera
• Method 1
• Take a spare body cap for your DSLR and drill a
hole in the center approximately ¼ of a inch in
diameter.
• Tape a thin piece of aluminum (cut from a soda
can) over the hole in the body cap.
• Twist a sewing needle through the aluminum
patch. Trying to make the hole as smooth and
small as possible.
Pin Hole Camera
• Put the body cap on the camera. And proceed to
take photographs through the pin hole
Doing the math
d= 1.9 sqrt ( 50mm * 550nm)
= 1.9 sqrt ( 0.05m *0.00000055m)
= 0.3mm
F = f /d
= 50mm/0.3mm
= 166
The aperture is F166 when the diameter of the pin hole is 0.3mm
at a focal length of 50 mm
Exposure is
Time ½ second
Aperture f unknown
ISO 3200
Pin Hole Camera
• By moving the pin hole further away from the
image sensor the image can be enlarged
Pin Hole Camera
Exposure is
Time ½ second
Aperture f unknown
ISO 3200
Pin Hole Camera
• Some tips
• The sharpness of the image is determined by
the size of the pin hole, its roundness and the
thickness of the material that the pin hole is in.
There is no focusing.
• Exposure times will be long. Use a tripod if
possible.
• Camera will need to be on the manual mode so
that the shutter will operate.
An Alternative method
• Use tin foil to cover the front of the camera.
• Form the tin foil onto the front of the camera so
that no light gets into the camera body.
• Be very careful not to short out any electrical
contacts in the camera body with the tin foil.
• Use tape to protect the electrical contacts.
• Gently put a small hole in the tin foil, in the
middle of where the lens would be.
• What happens if you have two holes?
Tin Foil
Lens removed
Gently make a small
hole here with a
straight pin or
needle
Form the tin foil
into the camera
body so that no
light can enter
into the body of
the camera
Some Pictures
Exposure is
Time 1/13 second
Aperture f unknown
ISO 200
Shari Foreht
Exposure is
Time 1/15 second
Aperture f unknown
ISO 3200
Exposure is
Time 1/8 second
Aperture f unknown
ISO 3200
Exposure is
Time 1/8 second
Aperture f unknown
ISO 3200
Exposure is
Time 1/30 second
Aperture f unknown
ISO 3200