"nighttime fire performances" are you talking about? If you are referring to something along the lines of the South Pacific type fire dances and you expect the camera to stay on the dancer and their torch, I would suggest that this environment is not what I would consider low-light. The torches are relatively bright. If, however, you were to try and focus on someone standing 10 feet (or more) away from the dancer/torch, then that *would* be lowlight.
If you are referring to some other sort of "nighttime fire performances" that uses less than brightly burning torches, then I would need to understand what that is in order to decide whether the brightness of that torch actually constitutes "low light". If this is what you are looking for, $400 is not going to get you very far.
"Decent audio" is a relative term. You will need to learn to use the manual audio controls. If the music is for the South Pacific type fire dances and if you have ever attended a show, you will know that there are certain very soft passages (usually at the start) and VERY LOUD passages (middle and end). The camcorder's auto audio level circuit will have issues dealing with that dynamic range. The loud portions will likely sound muddy and the soft portions will have a whooshing sound characteristic of the auto audio leveling circuit trying to do its job. When you are in manual audio mode, the whosshing will likely go away - and you need to turn down the level when the drums get going.
An external mic is preferable, but the only camcorder in your $ range, I think, that allows for an external mic jack is the Canon ZR800...
The built-in Sony "SuperNightShot" will drop into a green/white monochromatic mode - but only when you flip that switch. Not recommended for any use...
I am looking for a camcorder that would be suitable for filming nighttime fire performances.
Obviously, the camcorder would need to shoot well in low light situations - however, it should still be able to shoot color, not flip over to bw or "grainy green".
The camera will be at last 15 ft away from the performers, so I am not sure IR LED's would do it anyway.
Also, the camcorder should also record decent audio as music is part of the performances.
I am looking for a camcorder under $400.
What would you experts recommend? Grateful for any tips on this.

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