Updated the documentation to explicate that zero value in depth images is treated as unknown depth. This behavior is defined in a484d255b4/nerfstudio/model_components/losses.py (L242)
Co-authored-by: Matthew Tancik <matt@lumalabs.ai>
* documented coordinate conventions without a figure for now
* another sentence
* update frames docs
* explain intrinsics and extrinsics
* more comments
* fix build