Real frames from real films. You are going to measure the light in them —
the same number a cinematographer works to — and find out that high key and
low key are not opinions.
1 · Crush it2 · Meter it3 · Find the key
01Crush it
This is Barbie — about as brightly, evenly lit as a film gets. Drag the
slider. You are not changing the actors, the set or the shot. You are only widening the gap
between the light and the shadow.
1.5 : 1
High key
Bright, even, shadowless. Nothing is hidden because nothing is meant to be.
02Meter it
Six frames. On each one: click the brightest part of the face, then the
shadow side of the same face. Not the background, not the sky — the face. The whole
skill is knowing where to point.
Key side
—
Shadow side
—
Ratio
—
Click the lit side of the face.
Frame
Your ratio
Reads as
03Find the key
Last one. Look at the shadows — which cheek is lit, which way the nose shadow
falls, where the catchlight sits — and say where the key light was standing.
The camera is at the bottom of the circle, where you are.
SUBJECT
▲ camera
Where was the light?
✓That is lighting
Write this down. The difference between a sitcom and a thriller is a number:
the ratio between the key side and the shadow side of a face. Around 1:1 nothing is
hidden. Past 8:1 something is. Everything else — where the light stands, how hard it is —
decides what is hidden.
The frames. Stills taken from the scene library used across this course —
Barbie (2023), Se7en (1995), The Favourite (2018),
Vertigo (1958) and The Departed (2006). Shown for study and criticism.
Every number on this page is measured from the pixels in front of you, in your own browser.
For the teacher
Runs 12–15 minutes. Round 1 is the hook — the same frame slides from Barbie
to film noir on one slider, with the ratio counting up as it goes. Round 2 is the real work:
students meter six frames themselves and build a table of famous films by measured ratio.
The thing to press on in round 2 is where they point. A student who meters the sky
instead of the face gets a nonsense number, and that is the lesson — a light meter is only as
good as the decision about what to measure.
No sign-in, nothing stored, works on any device and for any class.
