The Keystone Calculator does its calculations based on a camera with a full frame 35mm sensor measuring 24mm by 36mm. This sensor has an aspect ratio (the ratio of the sensor height to its width) of 2:3. Cameras with full frame sensors include:

  • Canon 1D
  • Canon 5D 
  • Canon 6D
  • Nikon D4S
  • Nikon Df
  • Nikon D750
  • Nikon D810
  • Sony SLT A99

"Half Frame" Cameras

If you are using a camera with a smaller sensor such as in APS-C (or APS-H) sensor then when using the calculator you must enter the 35mm equivalent focal length of your lens, not the true focal length.

Cameras with APS-C sensors include:

  • Canon EOS 7D
  • Canon EOS 70D 
  • Canon EOS 60D 
  • Canon EOS 50D
  • Canon EOS 40D
  • Canon EOS 30D
  • Canon EOS 20D
  • Canon EOS 10D
  • Canon EOS 700D/Rebel T5i 
  • Canon EOS 650D/Rebel T4i
  • Canon EOS 600D/Rebel T3i 
  • Canon EOS 550D/Rebel T2i
  • Canon EOS 500D/Rebel T1i
  • Canon EOS 450D/Rebel XSi
  • Canon EOS 400D/Rebel XTi
  • Canon EOS 350D/Rebel XT
  • Canon EOS 300D/Rebel
  • Canon EOS 100D/SL1
  • Canon EOS 1100D/Rebel T3
  • Canon EOS 1000D/Rebel XS
  • Canon EOS D60
  • Canon EOS D30
  • Nikon D1H
  • Nikon D1X
  • Nikon D2H
  • Nikon D2Hs
  • Nikon D2X
  • Nikon D2Xs
  • Nikon D40
  • Nikon D40x
  • Nikon D50
  • Nikon D60
  • Nikon D70
  • Nikon D70s
  • Nikon D80
  • Nikon D90
  • Nikon D100
  • Nikon D200
  • Nikon D300
  • Nikon D300S
  • Nikon D3000
  • Nikon D3100
  • Nikon D3200
  • Nikon D3300
  • Nikon D5000
  • Nikon D5100
  • Nikon D5200
  • Nikon D5300
  • Nikon D5500
  • Nikon D7000
  • Nikon D7100

"Micro Four Thirds" Cameras

Cameras with a Micro Four Thirds sensor have a sensor that is a different shape to full frame and APS-C sensors. Four Thirds sensors have an aspect ratio of 3:4 as compared the 2:3 aspect ratio of full frame and APS-C sensors.

The Keystone Calculator does all its calculations based on an aspect ration of 2:3.

If you are using a camera with a Micro Four Thirds sensor then you must enter the lens focal length as the 35mm equivalent focal length, not the true focal length.

You should also specify a wider Border when preparing your group to allow for the fact that your camera's sensor is a different shape to the full frame sensor used by the calculator.

Cameras with Four Thirds sensors include:

  • Olympus E-5
  • Olympus E-1
  • Olympus E-3
  • Olympus E-30
  • Olympus E-620
  • Olympus E-600
  • Olympus E-500
  • Olympus E-510
  • Olympus E-520
  • Olympus E-300
  • Olympus E-330
  • Olympus E-450
  • Olympus E-400
  • Olympus E-410
  • Olympus E-420
  • Panasonic Lumix DMC-L10
  • Panasonic Lumix DMC-L1
  • Leica Digilux 3