Hi,

I exported the camera calibration and exterior orientation to use in ERDAS. I need the values in mm and I know that from the xml (exported from Metashape) the focal length, principal point (x,y) are in pixels.

Looking at previous post I found the formula

F(mm) = F(pixels) * SensorWidth(mm) / ImageWidth (pixel)

My data are the following

Image dimensions:

W 4000

H 6000

sensor size 23.44

Focal length 18.41

Principal point

x 1997.39

y 2997.48

I need to find out:

The pixel size in microns and from the camera model website I gather that is 3.89 microns

the focal length in mm, doing the formula I obtain

18.41*23.44/4000=0.1078

I was wondering how do I calculate the principal point in mm from my initial values?

Second question on the principal pont. Where is the PP in reference to? is it referring to the centre of the image/pixel array?

I have checked the manual but I couldn't find the formulas for those.

Many thanks.

Samantha