Chapter 35 — Exercises

Compositing is a doing skill with an unusually high ratio of judgment to technique: the hard part is not pulling a key, it's deciding whether an effect belongs at all and then making it disappear. These exercises train both. Most need only a phone, a few dollars of green cloth (or no screen at all), and free software — DaVinci Resolve's keyer and Fusion page do everything here at no cost.

Exercises are graded by effort and depth:

• ⭐ Warm-up — a few minutes; locks in a concept.
• ⭐⭐ Core — the real practice; do as many as you can.
• ⭐⭐⭐ Stretch — deeper or more ambitious; where the biggest gains are.

Model solutions and critiques for the starred and odd-numbered exercises are collected in Answers to Selected Exercises at the back of the book. Attempt each one before you read its answer.

A. Seeing the effect (Eye & Ear Training)

No camera — just your attention. This is the section that builds the eye compositing actually depends on.

1. ⭐ Count the invisible. Watch ten minutes of a modern drama or a polished commercial — something with no obvious effects. In your Frame Log, list every shot you suspect contains an invisible VFX: a replaced sky, a screen insert, a removed sign, a set extension, a cleaned-up reflection. You will find more than you expect. (Answer discusses what to look for.)

2. ⭐ Find the bad key. Search out three examples of a visibly bad green-screen composite (low-budget films, weather segments, and cheap ads are rich sources). For each, name the specific tell: green fringe, hard "sticker" edge, chewed hair, a subject not sitting in the background's light, or a matte that buzzes. (Answer provided.)

3. ⭐⭐ Where's the screen replacement? Watch any scene where characters use phones or laptops. Note which on-screen displays are likely replacements and what gives it away — or what makes it impossible to tell (glow, reflection, glare, tracking). Write one sentence on the difference between the convincing and unconvincing ones.

4. ⭐⭐ The light test. Pick one composite-heavy shot (any film with a fantastical location). Ignore the subject and study the light: does the light on the foreground character match the light of the world behind them — direction, color, hardness? Where a composite fails, this is usually why. (Answer provided.)

5. ⭐⭐⭐ Spot the synthetic. Find one piece of media publicly described as using synthetic media, de-aging, a digital double, or a voice clone (many are openly credited). Note whether it was disclosed, whether the person plainly consented, and whether it could mislead a viewer who didn't know. Map it onto the three questions from §35.6. (Model answer provided.)

B. Reading composites (Read the Sequence)

6. ⭐ Name the layers. Re-read FIGURE 35.1. On paper, draw the same three-part stack (foreground, matte, background) for a different shot: a weather presenter in front of a map. Label what's white, black, and grey in the matte. (Answer provided.)

7. ⭐⭐ Diagnose the field. In FIGURE 35.4 (the branded talking-head), THE LIGHT says the same soft, warm light is "painted into the background plate." Rewrite THE LIGHT and THE EFFECT as if the shooter had lit the subject hard and cool while the plate stayed soft and warm. What would the viewer feel, and why? (Answer provided.)

8. ⭐⭐ Read the matte. A described key: "In the black-and-white matte view, the background reads as dark grey with faint texture, the subject is solid white, and the hair edge is a thin clean grey." Name the one problem, its on-set cause, and the post fix. (Answer provided.)

9. ⭐⭐⭐ Write your own. Watch a scene you know contains an invisible composite (a set extension or screen replacement) and write a full Described Shot for it using all seven fields — but add an eighth note: "THE EFFECT (hidden): what was composited, and how you can tell (or can't)." This is the exact analysis Case Study 1 models.

C. Shooting the key (Shoot This)

The heart of the chapter. Even a bad first key teaches more than a chapter of reading.

10. ⭐ Hang a screen. Set up any green backdrop you can — cloth, paper, a painted board, even a solid-color wall that isn't in your subject's wardrobe. Get it as taut and wrinkle-free as you can. Photograph it under your lights and check: is the green one even value corner to corner, or are there hotspots and dark patches? Adjust until it's as even as you can make it. (Guidance provided.)

11. ⭐⭐ Two lights, two jobs. Shoot a 15-second clip of a person in front of your screen. Light the screen with even wash, and light the subject separately to match a background you have in mind (warm window room, cool office, whatever). Keep the subject 6–10 ft forward. Self-review: can you see green spill on their edges? Where? (Model self-critique provided.)

12. ⭐⭐ The distance experiment. Shoot the same subject twice: once pressed close to the screen, once 8 ft in front. Don't change anything else. Try to key both in post. Write down which keyed cleaner and exactly what went wrong with the close one. Keep both clips — they're the most persuasive argument for separation you'll ever run. (Answer discusses expected results.)

13. ⭐⭐ Shoot for the plate. Choose a real background image first (a photo of a room, a stock plate, a location still). Note its light direction, color, and hardness. Then light and shoot your subject to match it, and composite. The point: shooting to a known plate is far easier than compositing two things that were never meant to meet.

14. ⭐⭐⭐ The clean plate habit. Shoot a locked-off shot of a location with something in it you'll "remove" — a water bottle on a table, a sign, a person who walks through. Then, without moving the camera, shoot 5 seconds of the empty frame (the clean plate). In post, use the clean plate to paint the object out. Feel how a clean plate turns an hour of work into a minute.

D. Keying and compositing (Cut This)

Use DaVinci Resolve (free) or any editor with a keyer and masks. Appendix E translates the tool names.

15. ⭐ Pull your first key. Take any green-screen clip (your own from Section C, or a free sample). Apply the keyer, sample the green, and — before anything else — switch the viewer to show the matte in black-and-white. Describe what you see. Is the background pure black? The subject pure white? (Answer provided.)

16. ⭐⭐ The five-step clean. On that same clip, run the full order: pull the key → despill → clip black → clip white → shrink/soften the edge → composite over a background → grade together. Toggle each step off and on. Which single step made the biggest visible difference? (Model answer provided.)

17. ⭐⭐ Screen replacement. Shoot (or find) a clip of a hand holding a phone with a solid-color screen. Corner-pin track the four corners, pin in a replacement image, then add glow, a reflection, and a hint of glare. Self-review: does it track without floating, and does it throw light on the hand? (Answer provided.)

18. ⭐⭐ Stock element, matched. Composite a licensed light-leak or flare element (light-on-black) onto a clip using screen blend mode. Then match it: grade it to the shot, reduce its strength until it's a hint. Compare the maxed version to the restrained one. Which serves the shot? (Answer provided.)

19. ⭐⭐⭐ Roto by hand. Take a short clip with a moving subject and NO green screen. Rotoscope a mask around them for 20–30 frames — draw the shape, step forward, adjust, repeat — then composite them over a new background or apply an effect to only them. Write one sentence on why green screen exists.

E. Fixing the composite (Fix the Shot)

20. ⭐ Fix the fringe. A composited subject has a faint green glow around their hair and shoulders against a bright new background. Name the one post step that fixes it and the one on-set decision that would have prevented it. (Answer provided.)

21. ⭐⭐ Fix the shoot. A described failed key: "The subject stood right against a wrinkled green bedsheet lit by one lamp; the room was small. The key leaves green patches in the corners, a shadow behind the subject's head, and eats their dark hair." Diagnose every problem and give the specific fix for each, sorted by stage (pre / production / post). (Answer provided.)

22. ⭐⭐ Fix the sticker. A screen replacement "looks pasted on — the graphic is razor-sharp, sits flat on the phone, and the phone screen is the only thing in the shot throwing no light." List everything missing and how to add each back. (Answer provided.)

23. ⭐⭐⭐ Fix the mismatch. A sky replacement: the new sky is dramatic and gorgeous, but "the shot still looks wrong." The foreground is lit from the left; the new sky's sun is clearly on the right; the sky is razor-crisp over grainy footage. Prescribe the full fix, and state the general principle it teaches about every stock element. (Model answer provided.)

F. Settings and scenarios (Settings Drill)

24. ⭐ Read the box. Without looking, reconstruct the §35.2 Settings Box: name the eight things it specifies (screen, screen light, subject light, exposure, shutter, lens/DoF, white balance, codec) and give the one-phrase reason each matters. (Answer provided.)

25. ⭐⭐ Write the capture settings. For each shoot, write the key capture choices (format/codec, shutter, exposure of the screen, separation) and the one thing that most determines a clean key: (a) a phone-only green-screen interview; (b) a product shot where a phone screen will be replaced; (c) a fast-moving subject you'll have to roto. (Model answers provided.)

26. ⭐⭐ Match the plate. You're compositing a subject into three different plates: a warm café by a window, a cool modern office, and an outdoor overcast street. For each, specify how you'd light the subject (key direction, color, hardness, contrast ratio) to belong there. Pull directly on Chapters 11–13. (Answer provided.)

G. Recreate It & Five Ways

27. ⭐⭐ Recreate the invisible. Pick one invisible-VFX technique from Case Study 1 (a face/element you'd never notice) and reproduce its spirit at home: a simple set extension (widen a room with a photo), a removed object via clean plate, or one person appearing "twice" in a shot via a locked-off split. Judge it only by "can a friend tell?"

28. ⭐⭐⭐ Five Ways: one composite, five matches. Composite the same keyed subject over five different backgrounds — warm room, cool room, bright exterior, dark interior, and a graphic/branded plate — grading and lighting-matching the subject to each. Watch all five. Which match is most convincing, and what specifically sold it? (Answer discusses the trade-offs.)

H. The ethics of synthetic media

This section is not optional. The judgment here matters more than any key you'll pull.

29. ⭐⭐ Run the three questions. For each scenario, walk the §35.6 decision (consent → impersonation → disclosure) and decide: proceed, disclose, or stop. (a) De-aging an actor who signed off, in a fiction film. (b) Cloning a politician's voice to make them "say" something they didn't, for satire posted as news. (c) Using a synthetic voice — with the person's consent — to restore narration for a creator who lost their speech. (d) Compositing a real customer's face into a testimonial scenario they never filmed. (Model answers provided.)

30. ⭐⭐ Write the disclosure. For one legitimate but potentially-misleading use (say, a disclosed voice clone in a documentary), write the actual on-screen or verbal disclosure you'd use — one or two sentences that keep the audience's trust. Then say where in the piece it appears and why. (Answer provided.)

31. ⭐⭐⭐ The consent record. You're producing a branded piece that will use a spokesperson's likeness in a composite and possibly a synthetic version of their voice for pickups. Draft the checklist of what you must get in writing before you shoot (tie to releases, Chapter 38) so that both your ethics and your liability are covered. (Model answer provided.)

I. Interleaved & Synthesis

32. ⭐⭐ Interleave: light, capture, key. In three bullets, connect one idea each from Chapter 11 (lighting), Chapter 3 (codecs), and this chapter, into a single rule for shooting a clean key. (Answer provided.)

33. ⭐⭐ Interleave: grade the composite. After compositing, why do you return to the Chapter 32 skills — the vectorscope, the flesh-tone line, one shared grade? Explain how a great grade rescues a merely-okay composite, and why an ungraded composite always reads as fake. (Answer provided.)

34. ⭐⭐⭐ The "should I?" audit. Take your Project 3. List every effect you're tempted to add. For each, write the one sentence of why the story needs it. Cross out every effect whose sentence is weak. What's left is your actual VFX list — motivated, and no more. This is the whole chapter as a decision.

35. ⭐⭐⭐ Teach it back. In about 200 words, explain to a beginner why "the best visual effect is the one you never notice," using the alpha/matte idea, one on-set discipline (lighting or capture), and one example of an invisible composite. Teaching it is the strongest test that you own it. (Model answer provided.)

J. Going further (Stretch)

36. ⭐⭐ Cut This: the restrained overlay montage. Build a 20–30 second montage from your own footage, using two or three licensed light-leak or flare stock elements (light-on-black, screen blend mode) as transitions between shots. The discipline: each element must be a hint, graded to the shot, never a full-strength flash. Watch it back and cut any overlay you notice — you should feel them, not see them. Confirm every element is licensed.

37. ⭐⭐⭐ Shoot This: the window replacement. Seat a subject beside a real window whose view is blown out or dull. Expose for the subject (let the window blow), then in post track and replace the window's content with a plate (a better view, a branded graphic, weather), and add back a soft glow and the window frame's edge. This is a real, everyday commercial fix — a "screen replacement" for glass. Self-review: does the new view sit behind the glass, or float on top of it? (Model answer provided.)

38. ⭐⭐ Read the Sequence: what the grade holds together. Re-read FIGURE CS2.7 (the composite as layers). In writing, describe exactly what would look wrong if you skipped the final "grade the stack as one" step — name three specific tells a viewer would register, even with a flawless key.

39. ⭐⭐⭐ Recreate It: the invisible performance join. With a locked-off camera and unchanging light, shoot two takes of yourself (or a subject) delivering the same short line. In post, split-composite the best half of one take with the best half of the other into a single "perfect" take, hiding the seam. This is the exact invisible VFX of Case Study 1's FIGURE CS1.4. Judge it by: can anyone tell it's two takes? (Model answer provided.)

40. ⭐⭐⭐ Synthesis: your synthetic-media policy. Write a one-paragraph policy for your own channel, business, or classroom on the use of synthetic media — how you'll handle consent, when you'll refuse impersonation, and how and where you'll disclose. Make it specific enough to actually follow on a real job. Keep it; as AI tools land in your editor, this paragraph is the difference between principled and improvised.

When you've done these — especially the shooting and keying ones, and the ethics scenarios — you can make an effect appear and, more importantly, make it disappear. You've also built the judgment to know when not to. That judgment is the finish. Move on to Chapter 36, where we take everything you've finished and deliver it to the world at the right spec, with captions, and keep a master you'll never regret having.