coordinate system for SfmCamera values?

I am trying to extract camera positon and pose from the cameras in a component via the SDK.  I got part of the way there using info in this post:

https://support.capturingreality.com/hc/en-us/community/posts/115003056912-Determining-reconstructed-3D-point-x-y-z-coordinates-using-input-image-x-y-coordinates

So I can now access the cameras and get their focal length (sfmCamera.K.K.focallength).  But the values are all different from those given by the GUI for the same image set.  The difference is an ~ constant ratio of 35.  Is the focal length normalized to 35mm as a rule, or is this scaling determined by some other factor or transformation?

Next I will be looking at the Camera positions and orientations (from ISfmCameraModel and SfmCamera.R). Are these values stored in model space, or some other coordinate system?

Greetings.

Yes, the focal length is normalized against 35mm, i.e. SfmCamera::K.K.focallength == 1.0f equals to 35mm.

Both sfm points and sfm cameras are in sfm space, i.e. the same one.