I have a camera with these specs Image sensor = 1/4' OV CMOS Sensor Image Resolution: 1280*1024,640*480,320*240,160*120 Focal Length: 2.8mm Angle of view: 120

Since it's a 1/4 CMOS i got the width and heigth from here: http://www.photoreview.com.au/tips/buying/unravelling-sensor-sizes I calculated the horizontal and vertical angle of view and they give me 65 and 51 respectively. Equation Then why does it say in the specs that the angle of view is 120? Am I doing something wrong? Help Please.

  • \$\begingroup\$ Is the sensor possibly not a 3:2 aspect ratio, which would change the assumption about the length of the diagonal? \$\endgroup\$
    – twalberg
    Oct 30, 2017 at 20:46
  • \$\begingroup\$ I honestly don't know since that's the only information I got. \$\endgroup\$
    – Edumcg
    Oct 30, 2017 at 22:04

1 Answer 1


The angle is usually specified for the diagonal, which gives us 77°. This is still less than 120° which means the lens is not rectilinear.

Most likely a barrel distortion, common in fisheye lens - they need a different formula for the angle/focal length calculation.

barrel distortion


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