Chapter 12 — Quiz

Twenty-five self-check questions on quality, color, and ratio. Mix of multiple choice, true/false (justify your answer), short answer, and "what's wrong with this shot?" perception. Answer from memory first; the key and a topics-to-review map are at the end.

Multiple choice

1. What actually determines whether a light is hard or soft? A. The wattage of the fixture B. The apparent size of the source as seen from the subject C. The brand and price of the light D. The color temperature of the light

2. You want to make a small hard lamp produce softer light. Which does not work? A. Shoot it through a diffusion sheet B. Bounce it off a white wall C. Move it much farther from the subject D. Bring the softened source closer to the subject

3. Which is the warmest light? A. 6500K B. 5600K C. 3200K D. 7500K

4. Your subject looks too blue on the monitor under a daylight source. To neutralize it, you should set the white balance number: A. Higher (cooler) B. Lower (warmer) C. To auto D. It can only be fixed in post

5. A CTO gel is used to: A. Cool a warm tungsten source toward daylight B. Warm a cool daylight source toward tungsten C. Remove a green cast from fluorescent light D. Add a saturated creative color

6. CRI tells you: A. How bright a light is B. The color temperature of a light in kelvin C. How accurately colors render under the light D. How much a light flickers on camera

7. A key-to-shadow difference of 2 stops is a ratio of about: A. 2:1 B. 4:1 C. 8:1 D. 16:1

8. Which describes low-key lighting? A. Bright, low-contrast, shadows filled almost to nothing B. High-contrast, shadow-dominated, selective light C. Any footage that is underexposed D. Light with a low color temperature

9. Negative fill means: A. Adding a second fill light on the shadow side B. Placing a black surface on the shadow side to absorb light and deepen the shadow C. Dimming the key until the whole scene is dark D. Using a gel to subtract color

10. The main reason a bi-color LED panel is convenient is that it lets you: A. Run without any power B. Dial the color temperature on the fixture itself C. Guarantee a high CRI D. Eliminate the need for diffusion

11. You must shoot creative color (a saturated gel) and it needs to look clean, not muddy. Buy the light with the best: A. Maximum brightness B. Battery life C. CRI D. Beam angle

12. Which single tool most reliably lets you measure a lighting ratio instead of guessing it? A. The histogram of your still camera B. The waveform (or false color / a light meter) C. Auto white balance D. The rear LCD at full brightness

True / False — justify your answer in one sentence

13. The sun produces soft light on a clear day because it is physically enormous. T / F

14. Softer light is generally dimmer light. T / F

15. Auto white balance is the safest choice for a locked-off interview you plan to grade. T / F

16. Low-key lighting and underexposure are the same thing. T / F

17. A gel placed over a low-CRI light can still produce a rich, accurate color. T / F

18. You make a shot moodier mainly by adding light to the shadow side. T / F

19. You can safely tape colored cellophane directly onto a hot tungsten bulb. T / F

Short answer

20. In one sentence each, define diffusion and a softbox, and say how they are related.

21. Name the two axes of a light's color that §12.3–12.4 described, and give the gel or control you'd use to fix each.

22. A director asks for "friendly and trustworthy." What approximate ratio and lighting approach (high- or low-key) do you choose, and why?

What's wrong with this shot?

23. A described talking-head: the subject is lit with a soft key, a full fill, and a rim; white balance is correct; everything is technically clean — but the piece is meant to feel intimate and serious and instead feels like a bright corporate explainer. Name the single problem and the fix.

24. A described clip: an interviewer set the camera to auto white balance and the subject gestures a lot; across the answer, the subject's face drifts warm, then cool, then warm again. Name the cause and what should have been done on set.

25. A described "neon night" shot: a shooter used a cheap RGB light at deep blue, but the blue is grey and lifeless and the subject's skin looks sick even in the lit areas; the camera and the gel color are correct. What's the hidden culprit, and how would you prevent it next time?

Scenarios and decisions

26. A director wants a talking-head that feels "tense and serious." Give your three key decisions — quality of the key, approximate ratio (in stops or as a ratio), and whether you'd add fill or negative fill — and one sentence on why.

27. You're lighting a product for a commercial and it needs to look premium. Would you choose a hard single raking light or a flat, fully-filled soft light? Justify the choice in terms of ratio and what "premium" reads as.

28. You have one high-CRI bi-color LED panel, a white foam board, and a black foam board. Describe how you'd get (a) a friendly high-key look and (b) a moody low-key look from that exact kit — same panel, different result.

29. True or false, and justify: "To make a shot moodier, the first thing you should reach for is a brighter, harder light."

30. A shot looks great to your eye on the camera's bright rear screen, but you're told to measure the lighting ratio before you commit. Which tool do you use, what exactly do you read on it, and why not just trust the screen?

Answer Key

Reveal answers and explanations 1. **B** — hard/soft is set by apparent size at the subject, nothing else. (§12.1) 2. **C** — moving a source *farther* makes it appear *smaller* → *harder*. The other three all enlarge the apparent source. (§12.1–12.2) 3. **C** — 3200K; lower kelvin = warmer. (§12.3) 4. **B** — too blue means the WB number is set too high for the light; lower it to warm/neutralize. (§12.3) 5. **B** — CTO (Color Temperature Orange) warms daylight down toward tungsten. (§12.4) 6. **C** — CRI is color-rendering accuracy vs. a reference, not brightness or kelvin. (§12.4) 7. **B** — each stop doubles, so 2 stops ≈ 4:1. (§12.5) 8. **B** — low-key is high-contrast and shadow-dominated (not merely "underexposed"). (§12.5) 9. **B** — negative fill absorbs spill on the shadow side to deepen it, adding no light. (§12.5) 10. **B** — bi-color = adjustable color temperature on the fixture. (§12.6) 11. **C** — clean creative color needs a high-CRI (honest-spectrum) source. (§12.4) 12. **B** — the waveform/false color/light meter measures the key-vs-shadow gap in stops. (§12.5, 🔗 Ch. 5) 13. **False** — the sun is hard on a clear day; it appears as a *small point* because it's so far away, and small/distant sources throw sharp shadows. (§12.1) 14. **True** — softening spreads the same energy over a larger area, so soft = dimmer. (§12.2) 15. **False** — AWB *drifts*, changing the subject's color mid-shot; a fixed kelvin (or gray-card) balance is correct for anything you'll cut/grade. (§12.3) 16. **False** — low-key exposes the *key-lit skin correctly* and lets shadows fall deliberately; underexposure makes even the bright areas murky. (§12.5) 17. **False** — a gel can only tint the spectrum it's given; over a low-CRI source the color comes out muddy. (§12.4) 18. **False** — you go moodier by *subtracting* fill (or adding negative fill), deepening the shadow, not by adding light. (§12.5) 19. **False** — cellophane/plastic gels can melt or ignite on a hot bulb; gel hot lights only with proper heat-resistant material at a distance, and note LEDs run cool. (§12.2, 12.4, 12.6) 20. **Diffusion** is any translucent material placed between a light and the subject to scatter its rays and enlarge its effective size (softening it); a **softbox** is a fabric enclosure that mounts over a light and shoots it through a front diffusion panel — i.e. a contained, controllable diffusion modifier. They're related because a softbox *is* engineered diffusion with black sides to control spill. (§12.2) 21. Axis 1: **warm ↔ cool** (blue/orange), set by **color temperature** in kelvin (white balance, or a CTO/CTB gel); Axis 2: **green ↔ magenta** (tint/CC), fixed with a **minus-green (magenta) gel** or the tint control in post. (§12.3–12.4) 22. Aim **~2:1 (about 1 stop)**, a low-ratio / **high-key-leaning** approach with a soft key and open shadows — low contrast reads as safe, open, and friendly. (§12.5) 23. The problem is the **ratio**: it's too low/flat for the intent. Fix: raise the ratio — subtract fill or add **negative fill** so the shadow side deepens (toward 4:1 or more), possibly warm the key. Mood lives in the shadow, and this shot has none. (§12.5) 24. Cause: **auto white balance** re-guessing as the framing/reflected color changes. On set, set a **fixed kelvin** WB (or shoot a gray card and match to it) and turn AWB off. (§12.3) 25. The culprit is the **low-CRI source** (cheap RGB light with a poor spectrum): it can't render a clean blue or honest skin no matter the gel or camera. Prevent it by using a **high-CRI (95+) light** (and correct any green cast before adding creative color). (§12.4) 26. A **hard-ish key** (raked from the side for defined shadow), a **high ratio (~4:1 to 8:1, i.e. 2–3 stops)**, and **negative fill** (a black card) rather than fill — because tension and seriousness are built by shadow and contrast, not by adding light. Expose the key-lit skin correctly and let the shadow fall. (§12.5) 27. A **hard single raking light** with a fairly high ratio. "Premium" reads as shape, texture, and controlled shadow — a hard raking light sculpts the product and creates rich, contrasty falloff that says "luxury," whereas a flat fully-filled look reads as generic/catalogue. (High-CRI is assumed either way, §12.4/12.5.) 28. (a) **High-key:** use the panel as a soft key (diffused/close), and place the **white** board on the shadow side to bounce fill in, lifting the ratio toward ~2:1 — open and friendly. (b) **Low-key:** move the panel to a steeper side angle (harder), and swap in the **black** board as negative fill so the shadow deepens toward ~8:1 — moody. Same panel; the *board* decides the mood. (§12.2, 12.5) 29. **False.** The first thing to reach for is usually *less* light on the shadow side — subtract fill or add negative fill to deepen the shadow. Mood is built by controlling darkness, not by adding brightness; reaching for a brighter/harder key first is the classic beginner reflex that produces harsh, not moody. (A harder key *can* help shape a high ratio, but the ratio — the dark — is the point.) (§12.5) 30. Use the **waveform** (or false color, or a light meter). Read the **brightness of the key-lit side versus the shadow side**; the vertical gap between the two traces, in stops, *is* your ratio. Don't trust the rear screen because its brightness and your eye both lie — the same shadow looks different on different monitors and at different screen brightness, so an "eyeballed" ratio won't survive to the edit or match the next shot. (§12.5, 🔗 Ch. 5)

Topics to review by question

  • Hard/soft & apparent size: Q1, Q2, Q13, Q14 → §12.1
  • Diffusion, bounce, modifiers, softbox: Q2, Q19, Q20, Q28 → §12.2
  • Color temperature & white balance: Q3, Q4, Q15, Q24 → §12.3
  • Gels, CRI, color accuracy: Q5, Q6, Q11, Q17, Q19, Q21, Q25 → §12.4
  • Lighting ratio & mood (high/low-key): Q7, Q8, Q9, Q12, Q16, Q18, Q22, Q23, Q26, Q27, Q28, Q29, Q30 → §12.5
  • LED panels & the kit: Q10, Q19, Q27 → §12.6
  • Prior-chapter links: stops & scopes (Q7, Q12, Q30 → Ch. 5); three-point roles behind ratio (Q22, Q23, Q26 → Ch. 11).

Scoring guide: 27–30 correct = you can walk onto a set and author mood on purpose. 21–26 = solid; re-read §12.5 (ratio) and §12.4 (CRI). Below 21 = re-read the chapter and, more importantly, shoot the one-face-four-moods lab in Case Study 2 — this material lives in the hands, not the head.