Lavs > mixer > xlr into camera or...
 

I`m curious to the pros and cons of using lav mics and a boom, running them through a mixer, then into the camera (i`d assume through the XLR ports) VS. using a separate sound recording device. (I am not a sound guy but need to understand these things as I want the film to have the best I can make it)

You can get better sound with a better recorder than with most cameras. You have to sync the sound in post and that is time consuming.

If your mics, mixer and technique are crap, a separate recorder won't help you.

Regards,

Ty Ford