Two pass encoding, also known as multi-pass encoding, is a video encoding strategy used to retain the best quality during conversion. In the first pass of two-pass encoding, the input data from the source clip is analyzed and stored in a log file. ... Two-pass encoding is almost twice slower than one-pass coding.

What does two pass rendering do?

What 'Two-pass' does is kind of render your video twice, effectively doubling the upload time.

Which is better VBR 1 pass or VBR 2 pass?

2 pass optimizes bitrate so it makes smaller file with about the same quality as 1 pass. VBR makes also smaller file than CBR because it uses only the bitrate it needs. Static scenes uses very low bitrate with VBR but CBR uses max all the time. Thank you very much.