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Does someone know the field of view values for the new iPhone4 camera? I'm doing some AR app's, and I want to know the horizontal and vertical angle of the rear camera.

Thanks!

skaffman
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mguellsegarra
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  • The one in the front or back? – kennytm Aug 29 '10 at 09:19
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    @KennyTM - question says "the horizontal and vertical angle of the rear camera" – Gareth Aug 29 '10 at 09:35
  • Yes... the the back camera. I've calculated with a ruler (making "atan" with distance between ruler and iphone camera, and distance of the ruler) and I've got a angle of 23.54, but it seems too small... What i'm doing wrong? – mguellsegarra Aug 29 '10 at 09:44
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    I've found this: iPhone 4 main camera: 4.54 x 3.39 mm^2 chip (5.67 mm diagonal) 5.0 Mpixels (2592 x 1936) 1/3.2" back-illuminated CMOS sensor 4:3 aspect ratio 35 mm film camera crop factor: 7.64 Low ISO 80 (or better) 3.85 mm lens focal length f/2.8 lens aperture Autofocus: tap to focus (from: http://falklumo.blogspot.com/2010/06/apple-iphone-4-camera-specs.html) And I'm trying to calculate the angle with http://www.tawbaware.com/maxlyons/calc.htm , but I don't understand a lot of things... – mguellsegarra Aug 29 '10 at 10:08

3 Answers3

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If the sensor is 3.39 mm tall (referenced to landscape mode), then half that is 1.695 mm. Focal length for the iPhone 4 is listed as 3.85 mm. atan(1.695/3.85) is 23.75 degrees from center to top, or 47.5 degrees top to bottom.

For the longer dimension 4.52/2 = 2.26 mm, atan(2.26/3.85) = 30.41 center to side, or 60.8 degrees left to right (again referencing with respect to landscape orientation).

So 60.8 degrees horizontal by 47.5 degrees vertical.

ADDED much later:

The focal length for the newer iPhone 4S back camera is listed as 4.28 mm, but with the same sensor dimensions as the older iPhone 4. So:

2*atan(2.26/4.28) = 55.7 degrees, by 2*atan(1.695/4.28) = 43.2 degrees

or roughly a 4 to 5 degree smaller field-of-view compared with the iPhone 4.

ADDED much much later:

The sensor size for the iPhone 5S back camera is reported to be 4.89 x 3.67 mm, with a focal length of 4.12 mm. Thus:

2*atan((4.89/2)/4.12) = 61.4 degrees wide

2*atan((3.67/2)/4.12) = 48.0 degrees top to bottom

...or an FOV just a smidge larger than the back camera the iPhone 4.

hotpaw2
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  • Nice info hotpaw2! I'm making an AR app using AVFoundation overlay camera, and there the camera image is like the video record on iPhone 4 (is cropped compared with the still camera). I think that this calculations there are not right at all... If the camera has 60.8 degrees horizontally (in landscape), and the app has 480 pixels width, can we say that one degree equivals to 7.89px ? – mguellsegarra Aug 31 '10 at 06:15
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    @scummbar have you tried with the 'default' values that are always set in `glFrustum` in a sample OpenGL ES demo app? – rano Sep 05 '10 at 12:24
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    @VansFannel : iPhone 4S calculation added. – hotpaw2 Jan 22 '12 at 20:07
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    Out of interest, how come the pARk sample code uses FOV = 60.0 in portrait mode? That doesn't seem to agree with the values above - or maybe I conflating two separate concepts around FOV? – stephent Feb 10 '12 at 21:51
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I think iOS7 has introduced a new property videoFieldOfView for AVCaptureDeviceFormat so we can use this property to get the FOV, field of view like:

NSLog(@"Camera's FOV is %f",myCamera.activeFormat.videoFieldOfView);

where myCamera is an instance of AVCaptureDevice. Here you will get an overview on focal length, angle of view and field of view.

makboney
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  • i didn't know about this! i ran a quick test on the front camera of an iphone 5, and the number closely matches the measured value here http://www.boinx.com/chronicles/2013/3/22/field-of-view-fov-of-cameras-in-ios-devices/ (iOS reports 54.370, blog post measurement was 54.2). – bunnyhero Sep 21 '14 at 06:51
  • Yes, i got the same for iPhone 4s and iPhone 5. But need to work on devices running on iOS 6.0+ or earlier :( – makboney Sep 21 '14 at 08:16
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Seems there is a little mistake in previous calculations OV8830-G04A sensor has dimensions 4592x3450 um

Then correct angles are:

2*atan(4.592/(2*4.28))*180/pi = 56.423

2*atan(3.450/(2*4.28))*180/pi = 43.903

It becomes very crucial in sensitive applications.

Nikolay Frick
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