pretty much any internal mic will produce useless sound due to location and quality. I wish the manufactures would just give up putting internal mics on pro equipment. It's just a complete waste of space and weight, plus it drains the battery
Agree with Uwe - I've done live music videos and having any kind of basic on-camera recording aids enormously in syncing the sound with whatever pro sound gear you have set up to get the "real" audio.
we always doing voice dubbing ,so if have a pilot track capture from internal mic very easy to dubbing,when we r doing dubbing ,we give the artist a pilot track via a head phone,then artist maintain same modulation and timing of pilot track,very easy to audio dubbing,all Bollywood films are doing this way,so we are don't bother about sound recording in the field,just record the pilot track,
thanks