Natron - automatically adjust render frame range How do I set the frame range to automatically adjust to current video input?



Explanation:

I did some color correcting in Natron and I wanted to reuse the project for other video files so I changed the reader input destination. However, the second video was rendered with the frame range of the previous video. This resulted in, in this case, wastefully long render process as the original video was longer, flow of errors and practically useless output.
Go to the writer properties and change the "Frame Range" value from "Project frame range" (or less probably "Manual") to "Union of input ranges".

This, as the name indicates, determines the frame range as the union of inputs you pass to the writer.