Most “broken tracking” reports we see are environment problems, not model crashes. This guide consolidates lighting science, desk setup, and troubleshooting into one playbook you can finish in a single evening. It replaces several thinner posts that used to cover the same ground separately.
Contents
1. What good tracking looks like
Before chasing a personal best, spend one untimed minute watching the skeleton overlay. You want:
- Both hands consistently detected (status not stuck on WAITING)
- Landmarks glued to fingers, not swimming around the wrist
- Palms facing the lens so the full hand silhouette is visible
- Hands remaining inside the frame at the top of each pump
If the skeleton looks healthy at 50% speed, only then raise intensity. Training on a bad signal teaches bad habits.
2. Lighting experiments (more important than camera price)
Computer vision models trained on everyday photos expect faces and hands to be brighter than the background, with visible edges. A cheap laptop webcam in good light often beats a 4K camera pointed at a silhouette.
| Setup | What we observed in playtests | Verdict |
|---|---|---|
| Window behind player (backlight) | Hands become silhouettes; frequent landmark loss | Avoid for scored runs |
| Overhead warm room light only | Eye sockets / under-chin shadows; palms dim | Usable, not ideal |
| Monitor glow only (dark room) | Noise, color cast, unstable edges | Poor |
| Desk lamp 45° front-side + ceiling light | Stable palms, few dropouts at moderate speed | Recommended |
| Ring light / softbox facing player | Best contrast; watch for glare on glasses | Excellent |
Clothing contrast helps: very dark gloves on a dark hoodie can reduce edge cues. Bare hands or lighter sleeves usually track cleaner.
3. Framing and distance
Target roughly 60–100 cm from camera to torso. Closer than ~50 cm and vigorous pumps exit the top of the frame. Farther than ~1.2 m and hand size approaches the engine’s minimum clamp, which can make thresholds twitchy.
- Include head + both hands with margin above the fingertips at max pump height
- Keep the camera near eye level; extreme low angles foreshorten palms
- One person in frame for serious attempts
- Clean background beats busy motion (TVs, walking people)
4. Desk ergonomics (comfort = consistency)
You will take multiple 20-second bursts. A painful neck ruins form by attempt three.
- Laptop: raise the screen with a stand or books so you are not hunched
- External webcam: center it above the display
- Elbows free—do not jam arms against chair rests while pumping
- Clear the swing zone of mugs and microphones
- Feet flat; a stable base reduces torso sway that confuses framing
For longer practice days, pair this with wrist warmups and safety.
5. Motion the detector likes
Remember the engine needs a directional reverse with travel ≥ about one-third of apparent hand size. That means:
- Prefer: open palms, alternating vertical pumps, modest amplitude, steady tempo
- Avoid: fists, hands edge-on, both hands moving in sync, wild lateral waving, pumps that leave the frame
If you are testing pure finger speed without camera drama, switch to keyboard 6/7 mode—scores are not mixed with webcam ranks in the same mental bucket.
6. Troubleshooting flowchart
- No camera image? Check browser permission, close other apps using the camera, try HTTPS (required on most browsers), reload.
- Image ok, both hands WAITING? Move closer, brighten front light, open palms toward lens, remove backlight.
- Hands detect but reps low? Increase vertical travel slightly, slow down 10%, ensure alternation, watch that hands stay in frame.
- Works then dies mid-run? Likely heat throttle or tab CPU fight—close background video calls, cool the device, shorten session.
- Still unreliable? Use keyboard mode for today’s training; fix environment later.
Browser quirks: Chrome/Edge are the most battle-tested path for getUserMedia + WebGL. If Safari blocks the camera, re-check site settings for 67game.store.
7. Pre-run checklist (print or screenshot)
| # | Check | Done? |
|---|---|---|
| 1 | Front light stronger than background | ☐ |
| 2 | 60–100 cm distance, both hands framed with margin | ☐ |
| 3 | Palms open toward camera | ☐ |
| 4 | Skeleton stable at slow speed | ☐ |
| 5 | Wrists warmed up 1–2 minutes | ☐ |
| 6 | Goal clear: form practice vs PB attempt | ☐ |