More optional metadata fields?

[cholmes]

Many satellite imagery providers use a lot of metadata fields, like azimuth angle, off-nadir / look angle, sun angle, local time of day, cloud cover, etc.

It could be useful to standardize those fields in some way, for interoperability. Perhaps make a fuller set of fields that providers could choose to use.

[matthewhanson]

I like the idea of having a fuller set of suggested fields, especially when it comes to viewing or sun angles to encourage the same conventions (otherwise you have some sources using declination, some zenith, or even "look angle").

But we'd also want to support completely optional and unique provider/data fields as well.