FPV Camera
🟢 Start — zero knowledge, plain words. 🟡 Hands-on — building or buying, specifics and tradeoffs. 🔴 Specialist — the physics and math behind it.
🟢 Start. The FPV camera is the drone's eyes — its only job is to send a live picture to your goggles. It's not the one recording pretty footage (that's the action camera); it exists to show the world right now. Two worlds to pick from: analog — a picture straight out of the 90s, but with minimal latency and a low price; digital (DJI, Walksnail, HDZero) — HD image, but pricier and locked into ecosystems.
🟡 Hands-on. Choosing a system means choosing an ecosystem — camera, transmitter and goggles must match:
| System | Goggle image | Typical latency* | How the signal fails |
|---|---|---|---|
| Analog | ~480p, static | ~5–15 ms | gradual — it "snows", but you still see |
| HDZero | 720p/90 | ~14 ms (fixed) | digital, but predictable |
| Walksnail | 1080p | ~22–32 ms | blocks/freeze on weak signal |
| DJI O4 | 1080p/100 | ~15 ms (Racing) – 30 ms | blocks/freeze on weak signal |
Indicative values — they depend on mode and goggle display. Beyond the system, look at: sensor size (better after dusk), FOV, and 4:3 vs 16:9 format (must match the goggle setting).
🔴 Specialist. Glass-to-glass latency is the sum of a chain: sensor exposure → (in digital) H.264/H.265 encoding → transmission → decoding → display. Analog doesn't encode at all — hence its latency edge and its "graceful death": noise grows gradually because the image isn't packetized. Digital adapts bitrate to link quality and freezes frames when data stops — which is why you fly with RSSI margin, not "down to zero". Rolling-shutter sensors plus frame vibration produce jello in the image: that's a mechanical problem (prop balance, camera damping), not an electronic one.