Camcorder Terminology Explained
Posted on 11/9/2009 12:15:00 PM
Talk about ND Filter, Gain, Shutter Speed and Aperture value affecting output.
Talking to a fellow videographer on using the Canon XH-A1 camera, I tried to explain what all these setting means,
ND Filter
ND (Neutral Density) filter can be used when there is strong light around to void over exposure. Adding the ND filter allows flexibility in setting the shutter speed and aperture settings.
Gain
Always avoid gain! Gain = Grain. It is an electronic noise added to the scene to boost brightness in a bad way. For XH-A1, I always suggest shooting -3db outdoor, and 0db indoor.
Shutter Speed
Increae the shutter speed will limit the amount of light enter to the sensor. The higher the shutter speed the less light goes into the sensor.
I have heard the movie "Saving Private Ryan" at the opening sequence, it adopts a very high shutter speed. So the scene looks very dim, crisp/sharp and no motion blur. This high shutter speed, it creates a strobbing effect. It tends to make viewer very uncomfortable. That's exactly what the director wanted to archieve.. to make the audience feel unsettleing to see this opening war seqeunce.
Aperture Size
Larger iris (lower Aperture/Av value) will allow more light to go into the sensor. It also add a fake "depth of field" feel similar to using a DOF adapter. If shooting outdoor with small Av value (thus large iris size), that will make the scene over-exposed. So the shutter speed need to be increased or or to apply the ND filter to limit the amount light. This trick is also called "Portrait" mode in many camera.
Did I get everything right? If not, please share your thought.