I recently recorded an interview where I believe I introduced some gain because of not enough light. I was plugged into a monitor and it looked fine on set but while capturing, I noticed it was not as clear. The footage was recorded on an hv20 as hdv, 29.97
I was hoping to get someone else's opinion - Is this a lighting issue ? A sample clip is uploaded here (click download at bottom of screen)
I won't download a blind clip, but if it looks "grainy" you can bet that is exactly what was happening... increased gain.
If you are in a low-light situation one of the very first things that the HV20 does is jack up the gain. Once it maximizes that, then it starts lowering the shutter speed in an effort to get a decently exposed image. No doubt your camera was increasing the gain.
It's hard to bypass that with the HV20, since there is no manual mode at all on the camera. The best you can do with it is "trick" it into a semi-manual mode by first establishing a scene where you know that gain is not increased and shutter levels are normal and then do an "exposure lock" to keep the auto-pilot from increasing them. Do some Googling and you'll find several tutorials on how to trick the camera... some using things like your cell phone screen to establish benchmarks for exposure.
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