The Three Functions of Light

(Cinematic Lighting Lesson 01)

Summary: Ryan covers the three functions that light plays in the creation of your images: separation, shadow, and fill.

Length: 4:02 minutes

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Depth of Field, Part 1: How Aperture and ISO Affect Focus
Your Guide To High Speed, Part 6: Five Tips For A Successful Shoot
Your Guide To High Speed, Part 5: Lighting Six High Speed Sets
Your Guide To High Speed, Part 4: Common Lighting Problems
Your Guide To High Speed, Part 3: Camera Operation & Workflow
Your Guide To High Speed, Part 2: Frame Rate
Your Guide To High Speed, Part 1: Introduction
12 Crucial Questions Before Lighting Your Set (Cinematic Lighting Lesson 15)
Negative Fill: The Best Kept Secret (Cinematic Lighting Lesson 08)
15 replies
  1. jonathanesters
    jonathanesters says:

    I appreciate the bird’s eye shots, lighting diagrams and tools list! As well, a concept was made clear here that was muddled prior; I am using light to create the illusion of 3D on a 2D image.

    • Tim
      Tim says:

      Thank you! We are adding more behind the scenes (BTS) cameras to better help everyone “see” everything that we do to create the the images on camera, so you can do the same (and more!). In some of the upcoming lessons, we recreated a living room and a kitchen in an empty studio. When you look at the bird’s eye shots, you’ll see we only did art decoration (“art dec”) in a corner of the room since our framing was very tight. This is another trick to keep budgets and time under control. 🙂

    • jonathanesters
      jonathanesters says:

      *muddled in my mind prior to watching this video e.g., what am I really doing with all of these lights?! Camera Foundations was empowering and I’m highly anticipating what’s to come here.

  2. kinopasha
    kinopasha says:

    I love how well those videos are put together! Well structured, very informative and straight to the point. I’ve used a number of online educational services in past couple of years and, unfortunately, most of those provide an interview-type, or a master-class type of content which are not the best for educational purposes. I just want to give you guys a HUGE thank you and tell you how much I appreciate your work, how thorough and clear that is.

    With deep respect, from a glittering snowy Moscow,

  3. price76
    price76 says:

    Hi guys I noticed the dog on the couch, can he be included on the next birds eye, appreciate it. Also what angle from the camera should the dog be placed?
    Jokes aside keep up the brilliant work.
    Dave 🙂

    • Ryan E. Walters
      Ryan E. Walters says:

      Awe, keen eye! Actually, the angle of the dog to the key light is integral to your lighting setup. If you don’t have him placed at the correct angle, you might as well give up and go home. 😉

      I’m glad you’re liking the tutorials- thanks for the support. 🙂


  4. price76
    price76 says:

    Hi Ryan

    In the 3 layers and closing diagram is the 4x 4 floppy working as a flag for the fill lite 200 key or as a large white soft diffusion modifier for it?


    • Ryan E. Walters
      Ryan E. Walters says:

      The 4×4 floppy is acting as a flag for the Fill-Lite 200. Since it is a soft light, it’s light rays bounce everywhere. By adding the flag it removes the spill of the light from the background and makes the shadows in the background darker.


    • Tim
      Tim says:


      At the current 720p resolution, the downloads are already quite large (in the hundreds of megabytes). If we made them 1080p, the file size would be more than most members’ connections could handle.

  5. Samjs
    Samjs says:

    In one of your youtube videos, you explain how valuable a light meter can be. When googling light meters with video, I find meters valuable when video recording with a DSLR camera. Since I am using a JVC GY-HM600 camera that does not have ISO, will a light meter still be of value? Are there other settings I need to use in the light meter equation in place of ISO?

    Thanks for your help!


    • Ryan E. Walters
      Ryan E. Walters says:


      Great question, yes a light meter is a very helpful tool to use for sure! I’m actually surprised that there are still video cameras out there that don’t use ISO. A lot of manufactures have switched over to using ISO, or at least let you change how the readout appears, whether it reads in gain or ISO.

      In any case, yes you can still use a light meter even if the camera only reads out in Gain, or if it doesn’t have and ISO/Gain adjustable settings. In either case, what you have to do is to calibrate the light meter and the camera together to figure out the ISO. Then you can set your light meter to that ISO and know it will match the camera. To do that, you need your camera, a gray card, and your light meter. Then follow the instructions I made for MasterLegend in the comments section of this video:

      If your camera doesn’t have a waveform, you can do the same thing by setting the zebras at 50% or 50 IRE. (But a waveform is going to be better.)

      Happy Shooting!

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