How to block background noise on canon sl2?
If it's a constant noise, like air conditioner blowers/fans, you can post process the audio to reduce the background noise. You need a small sample (a few seconds) of the time line where all you have is background noise to train the program. I've used this in Cool Edit. Cool Edit is now Adobe Audition. Audacity, a free audio editor, also has this feature under Effect -> Noise Reduction. Normally, you use a lavaliere on the person or a shotgun mic to reduce background noise when shooting the video.
Record sound separately using a portable digital sound recorder and swap it with the SL2's sound in the computer.
Record in a quieter environment.
Frank: not sure how, but this article explains how
not sure how, but this article explains how:https://www.guidingtech.com/26498/free-tools-remove-background-noise-audio/