2. Greenscreens
This is a mix of editing techniques and technology, that is
used to superimpose your subjects onto virtual
backgrounds, place them over animated backgrounds, or
transport them to any location that you may want.
It is a process called keying. This is where you isolate a single
color or brightness value in an electronic image and using
software to make that value transparent, allowing another
image to show through the affected areas.
Any color can be keyed, but green is most commonly used as
the subject is unlikely to wear green, opposed to a blue
screen where people are more likely to wear blue clothing.
3. How it works
First you need to buy a green (or other color) screen. These
can be relatively cheap.
You need to make sure that the lighting is smooth and from
different angles to make sure that there are no weird
shadows. Also make sure that there are no creases in the
screen, as if there is any it will make the new background have
creases in and will make it look odd.
Next you should import the footage into your timeline, on
whatever editing software that you use. Then apply a
chromakey filter onto the footage, this will offer you
adjustment options in the effects control panel. Your footage
should be at a 4:2:2 ratio as it is much easier to key than 4:2:0,
so make sure that the settings on the camera is correct.
I could use green screens if I need to film anything and have it
in a different location that I would not be able to get to in
person.
