Once you get outside the studio there are a lot more variables you will have to account when lighting your shot. A common situation is having multiple light sources that don’t exactly match in color temperature. This could be cool daylight from a window and warm tungsten practicals inside or it could be that two lights you are using have a slightly different native color temp and you want them to more closely match.
If you want to learn how to work with mixed color temperature lighting Jason J. Tomaric from FilmSkills has a quick set of tips and techniques that will help.
Probably the most common issue is having windows and doors in the background. Usually this goes beyond the dynamic range of modern digital cinema cameras and the best way to solve this issue is to use another light on your subject to balance the exposure. Now, if you use a tungsten light you’ll notice that it looks very warm compared to the natural daylight. It’s very noticeable and can make things look unnatural.
To correct changes where you just want to do a simple conversion from tungsten (~3200K) to daylight (~5600K) you can use a gel. A CTB (color temperature blue) gel is designed to do just that. The only thing to consider with gels is that you will lose some brightness with gels as they absorb light to make the color shift happen.
A modern alternative is to pick up a naturally daylight-balanced fixture for these scenarios. Or, better yet, get an LED with adjustable color temperature. Variable color lights will be able to be balanced in most situations as you can tune them to the exact shoot.
Honestly, if you are looking to purchase lights today you should just go with some LEDs. I’m not so convinced you need anything more than daylight-balanced LEDs to start (brighter and more color accurate than variable color temperature LEDs), but the new full color LEDs offer a much wider range of creativity.
Fairly basic and simple tip but very good to know if you are just getting starting in video production. This is something you don’t want to have to fix in post.