Colour Temperature

When using cameras colour temperature is very important when filming and taking pictures as if you want to create a certain feel or filter for an image you have to control it. An example of controlling colour temperature would be in most rom com films, as they all use filters on lights surrounding the scene to make the scene look warmer.

Colour temperature is measured in Kelvin (K). When the colour temperature is over 5000k it is called a cool colour, whereas when the colour temperature is at 2700-3000k the colours are warm colours. 4000k is moonlight, 6500k is daylight and 15000k is clear blue sky. 



Tungsten lights are 3800k, that is very similar to the colour temperature of moonlight, that is 4100k. 
When filming in the sun the light will change depending on what time of day it is, as it can be red, orange, yellow or white. You can set the white balancing automatically with most cameras as they zoom in on a certain white object to determine the lighting and colours of the rest of the image.

 On some more expensive cameras you can set it manually to your own settings, on these you can white balance on things that aren't white, like light blue for example to make the rest of the image seem warmer, doing this means you won't have to use lighting gel and filters. If you were to use a gel it would not last very long as they wear off and also could even melt after a while depending on the heat from the light.

Filters are used on lamps to change the look of what is on the camera and change the colour temperature coming from the lamp. 

If you wanted to create a warm scene for example you can use a tungsten light to light up the scene and then use a blue gel filter to filter through the light and then white balance the blue through the camera to make the scene look brighter , you can then remove the filter as the camera has been light balanced. But if you wanted to create a more cold darker feel for a shot you would need to use a dark blue gel filter to get the correct white balance.