epistemology is a big topic and we’re clearly operating on some contradictory premises/priors but I’ll continue to engage in good faith.
I think I’d consider the following as evidence of an event: photos/video, eyewitness testimony, and measurement data; each provided with provenance/traceability through the entire chain of reporting. Each reporting agent’s credibility on the topic plays a role in weighing the evidence.
Finally the believability (another big term) of the claim itself plays a important role in how much evidence is necessary for me to believe it. Here’s where I put on my internet atheist hat and reference the “Sagan Standard”: Extraordinary claims require extraordinary proof and it’s corollary: a claim asserted without evidence can be dismissed without evidence.