How Does Camera Autofocus Work?

Next Video:
How to White Balance a Camera....5

The autofocus on a camera uses a machine to automatically focus images for you. Learn how a camera autofocus works with help from a filmmaker and freelance editor in this free video clip.

Part of the Video Series: Filmmaking & Camera Tips
Promoted By Zergnet


Video Transcript

Hi guys. I'm Justin Z. I am an indepenedent filmmaker in Los Angeles, and I'm a freelance editor for the entertainment industry. I've been getting some basic questions about filmmaking including this one how does auto focus work. Well, basically auto focus should be called power focus because it uses a machine that automatically focuses the images for you. It's really convenient considering that tiny little cameras don't have any apparatuses to do manual focus so it's really important that the auto focus is there. So there are two types of auto focus. There is active auto focus and there is passive auto focus. Active auto focus has a little infrared beam inside the camera that will basically send light to the image and it will determine its focus based on distance, based on how much light there is and based on the position of the person and it will automatically determine it and then there's passive focus where it is usually used by DSLR cameras that actually uses the image on the sensor itself and figures out the actual focus by constantly zooming in and out and focusing until it finds it. So the infrared actually is better for focus, why they don't put it on DSLRs, no one knows but just the general idea is that it uses either an infrared beam or it uses pixels to figure it out, but either way it makes life more convenient for you. But to be perfectly honest if you're going to use a DSLR camera, use manual focus anyway, your eye is usually better than the computer. So that's all there is to it with auto focus on cameras. If you have any questions regarding this or other filmmaking, feel free to ask.


Related Searches

Is DIY in your DNA? Become part of our maker community.
Submit Your Work!