Simple answer , NO !

Because Nikon D3100 doesn’t have an external microphone jack on its body. Nikon D90 too , but fortunately Nikon has put one on Nikon D7000 body. Without it , for serious videographer Nikon D3100 is useless as an audio recorder. Yes , it does have built-in internal microphone but it is only records in Mono and does really good job on picking noise made when you focus or zoom the lens. Shutter sounds can also make quite a bit of noise.
zoom-h2-nikon-d3100-microphone

Read the rest of this entry »