Does getVerticalViewAngle() give actual Camera Angle Field Of View(CAFOV) value?

[Wm_Pooja]

I am utilizing a built in function named "getVerticalViewAngle()" to get the Vertical View Angle of Android Device Camera. The above function returns "63.8146" degrees as the Vertical Angle.

Now if I use the tablet on a tripod so that tilt is eliminated (Keeping tablet camera lens height as 900mm) and capture a picture of a wall at a distance of 1500mm, then 1800mm of the wall(vertical) is included within the picture. Calculating the Vertical Angle based on above scenario yields 61.9275 degress which is not equivalent to 63.8146.

Can anyone please explain why there is difference between Angle values?

 

[Overread]

The difference is probably because the setup is not 100% scientific nor perfect. I would say for an ap in a tablet its done pretty darn well to get that close a value; but it won't be perfect. The camera in the tablet might not be perfectly aligned; the tripod and tablet might have a tiny inaccuracy in its angle, the wall itself could have a tiny lean etc...

There are a lot of factors which could all add up to result in a difference in the angles.

 

[chris]

The difference is because the app probably calculates the angle with the lens focussed at infinity. As you focus at closer distances the angle decreases.