Most video editing programs have an option (somewhere) to sync external audio to the video's audio - the trick is that you should always record audio to the camera so you can sync that to the audio you recorded on an external device. One of the best investments you can make is a slate (clapperboard) to add a visual spike in the audio. From there you can manually sync the audio by lining up the spikes on the 2 audio tracks - the camera audio and the good audio, then just mute the camera audio. Keep in mind that video records audio at 48khz while most audio recorders default to 44.1khz, so you should switch it to 48khz to avoid syncing issues. Even without camera audio you can still sync the audio spike to where you see the slate claps closed on the video. Hollywood has been doing it that way for years. You can find a slate (clapperboard) on amazon for around $15. I recommend getting a dry-erase one as the chalk ones get a bit messy. I have both and prefer the dru-erase one because its a little bigger and it has color bars that can aid in color-corrwcting your video, but that's a while other discussion. As for software, PluralEyes seems to be the go-to program for syncing audio to video. I've used it and its pretty good. Once again, all software requires your video to actually have audio recorded with it or else there's nothing to sync to. I've used the sync audio option in Premiere with mixed results and usually end up just mnaully syncing the audio in the short films I shoot because I always slate every shot with a clapper for that exact reason. Davinci Resolve is a free video editor that's quite advanced and includes an option to sync audio although I've never actually tried it. I read somewhere that iMovie has a sync option too, but at the end of the day, a $15 clapper board means you can easily sync your audio regardless of what editing software you use, even if you don't record audio to the camera (but I steongly urge you to record it anyway to verify the syncing went as planned). As I mentioned, I shoot short films so I have a lot of experience with audio, and I used to own a small recording studio, so if you have any questions or need clarification, don't hesitate to ask. Hope that answers your question, Kenn
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