Some of the early beta tester YouTube videos have mentioned that Tesla told them the car only has storage space to save roughly 5-6 snapshots before uploading the data after the drive (I assume only on Wifi). They also said it wasn't a hard number of clips, so I'm guessing that means there is logic trying to decide how much video history to save in the clip based on what happened before the button was pressed, or the clips are compressed to a variable compression ratio depending on video content, or the storage is also used for something else that sometimes needs more or less space.
However, Tesla has been conspicuously silent on answers to these questions. We don't have any reliable info to tell us if the 5-6 snapshot limit even still applies (maybe snapshots are shorter now and take up less space?).
My speculation is that Tesla's silence indicates one or more of these things is happening (in order of how likely I think each is, most likely at the top):
- They need a good random and un-biased data set to train the neural nets, to avoid over-fitting on scenarios we think Tesla wants us to save, so they don't want to bias the data collection by giving any guidance
- They are already getting what they need, so why bother spending time to write up a communication to us all when they could spend that time continuing to make the software better
- There is some IP or privacy law liability concern with Tesla asking customers to send certain types of videos
- The button is a placebo. It was deployed to make use feel like we're helping, but it doesn't do anything
I'd tell you how I treat the button, but just in case #1 is correct above, I don't want to introduce bias into their data set.
As for emails, my philosophy is to send emails about snapshots only when I think it might not be obvious why I took the snapshot, or if it was a dangerous failure mode (running red lights, trying to pass a stopped school bus at full speed, etc.). When something like that happens, I take a mental note of the time and location, and jot it down in a notes app on my phone as soon as I finish the drive, then later I'll send the email whenever I get around to it. With maybe 15,000 or so people in the beta program now, I'm sure they get tons of emails, so I try to keep my emails clear, concise, and well formatted (I list the Date, Time, Location, and if a snapshot was saved at the top of the email). I usually show the location both by longitude/latitude coordinates and nearest address, because I'm not sure which they can use more easily.