# angle of view



## tonyk29 (Sep 3, 2014)

Hello,
I would like to know the angle of view of the rear camera of the ipad air (5MP)
The specs are as follow:
_focal length: 3.3mm
_aperture: f/2.4
_sensor type: CMOS active pixel sensor
_resolution: 2592 x 1936
Any help would be much appreciated
Thanks
Anthony


----------



## 480sparky (Sep 3, 2014)

It's not listed in the specs in the back of the manual?


----------



## WayneF (Sep 3, 2014)

tonyk29 said:


> Hello,
> I would like to know the angle of view of the rear camera of the ipad air (5MP)
> The specs are as follow:
> _focal length: 3.3mm
> ...




You would have to know the camera sensor size to calculate angle of view of the 3.3mm lens.

They do not say size, but it will be tiny.   All I can find is the iPad 3 sensor is 4.54×3.42 mm, which is near an 8x crop factor.

If you want to know, you can determine it.

Experiment with a measuring tape, and determine the field of view width that you can see at some few feet of focus distance distance.
Perhaps at exactly 3 feet, you see four feet 2 inches of width.
If you know trig, you can compute it.   Half this width is 2.08 feet,  2 x arc tan (2.08/3) = 69 degrees


Or, you can go to http://www.tawbaware.com/maxlyons/calc.htm

Go to the 4th calculator:  Dimensional Field of View Calculator

plug in 3.3mm lens, your focus distance, and start at around 8 for focal length multiplier.  Click Calculate and compare to your measured width.
Adjust the focal length multiplier until you get a more correct width that you measured.  You can enter decimals, like 7.92 for multiplier.
When you see your measured width, now you know focal length multiplier (related to sensor size).

Then in the 3rd calculator there: Angular Field of View Calculator

plug in 3.3 mm focal length, your now known focal length multiplier, and 4:3 phone compact image ratio.

This then tells you angular view of that lens.  I'm guessing near 65 degrees horizontal width.

Hope that is of any interest.


----------

