The camera is the whole reason the aircraft is up there, and if you pick it badly you’ve wasted every other decision you made. The question we get most often isn’t “which camera is best”. It’s “which camera answers the thing the inspection is asking”. A thermal sensor and an optical zoom camera answer different questions. Neither one covers for the other.
Quick answer: Thermal finds the fault and optical zoom documents it. A thermal sensor shows heat contrast, such as moisture under a roof or a hot joint on a line, while optical zoom adds real resolution at distance: the C20 carries 23x optical zoom with night vision, the C11 pairs 4K capture with digital zoom and tracking for moving targets, and the C12 puts a 2K visible camera and a thermal sensor on one three-axis head so a single flight returns a thermal map and a visual record of the same spot. The C01Pro stabilised gimbal is the lighter, cheaper option for plant protection and general looking. A heavier gimbal costs more flight time than its weight suggests, because holding it steady draws current. See the thermal inspection guide and the avionics guide.
| Payload | Sensor | Best for | Trade-off |
|---|---|---|---|
| C12 | 2K visible plus thermal, three-axis | One flight gives fault and record | Two sensors, more weight |
| C20 | 23x optical zoom with night vision | Detail at distance, night work | No thermal channel |
| C11 | 4K capture plus digital zoom, tracking | Targets that will not sit still | Digital zoom adds no new detail |
| C01Pro | Stabilised camera | Plant protection and general looking | Not an inspection payload |
Below we go through the two payload families, the case for carrying both at once, and the piece most buyers skip right over: the gimbal motors that decide whether the image is steady.
Choose the sensor from the task backwards
Start from what the inspector actually has to prove. A hot joint on a transmission line? That’s a thermal question. A serial number on a tower fitting? Optical zoom. Mapping a roof for moisture? Thermal. Documenting a bridge deck for cracks? Optical. The target picks the sensor. The price list doesn’t.
And if the job genuinely needs both, a dual-light payload answers it in one flight instead of two.
Thermal: what it actually sees
A thermal camera sees emitted infrared, so it reports temperature differences instead of colours. That’s why it’s so good at finding anything warmer or cooler than what’s around it: an overloaded conductor, failing insulation, moisture sitting behind a surface, a person in low light. It works no matter how dark the scene looks.
Resolution is where most people compromise. A low-res sensor gives you a coarse map that shows where the problem is, not what it is. Step up the resolution and you can see the shape of the fault itself. If the work is detailed defect finding, check thermal resolution before anything else on the spec sheet.
Optical zoom: the case for detail at distance
An optical zoom camera lets the aircraft keep its safe distance from the asset and still pull out detail. That’s exactly what you want next to live conductors, rotating machinery or anything unstable. The C20 carries 23x optical zoom with night vision for that job.
Keep optical and digital zoom separate in your head. Optical zoom moves real glass and holds onto real resolution. Digital zoom crops and interpolates: it looks bigger, but there’s no more detail in it. The C11 pairs 4K capture with digital zoom and intelligent tracking, which is the right call when the target won’t sit still.
Dual-light: carrying both at once
The C12 puts a 2K visible camera and a thermal sensor on one three-axis head, so a single flight gives you a thermal map and a visual record of the same spot. If the inspection has to hold up afterwards, and the thermal finding needs visual context, this is the one we see come back for. It removes the mismatch you get from two separate flights.
When the mission is just plant protection or general looking around, the simpler C01Pro stabilised gimbal is lighter, cheaper and does the same job.
Stabilisation: the gimbal is only as good as its motors
A gimbal is a control loop, and the motors are what drive it. Weak or slow motors show up as visible tremor, lag when the aircraft yaws, and drift in the wind. This is the part people skip. It’s also the part that decides whether your footage holds up as evidence.
The GB-series motors are sized to the payload mass. The GB36-1 KV50 and GB36-2 KV30 cover the smaller heads, and the GB54-1 KV33 and GB54-2 KV26 carry the heavier dual-light payloads. You’ll find them all under Gimbal Motors.
Weight and power budget
A gimbal isn’t just mass. It’s mass that has to be held steady, and that pulls more current than the weight alone would suggest. Hang a dual-light head on a small airframe and your endurance drops noticeably. Budget the payload’s weight and its current draw together, before you choose the airframe, then check the numbers against the endurance the mission actually needs.
Which payload for which job
Electrical inspection. A dual-light head, so every thermal finding comes with a visual record.
Structural detail. Optical zoom, so the aircraft stays back and still resolves detail.
Roof and moisture survey. Thermal, for the temperature contrast that shows what your eye can’t.
Agricultural scouting. A lighter stabilised gimbal usually does it.
If you want to know how the payload ties into positioning and the autopilot, that’s covered in RTK, gimbal and avionics integration, and the whole subsystem sits in the UAV avionics guide. The full catalogue is under Camera/Gimbal Series.
Frequently asked questions
Thermal or optical zoom for electrical inspection?
Thermal finds the fault. Optical zoom documents the spot. If you can only carry one, decide by what you have to hand over: a fault list or a photographic record, which is the split in our thermal inspection guide.
Is digital zoom as good as optical zoom?
No. Optical zoom adds real resolution. Digital zoom crops and interpolates, so you get magnification without any new detail.
Does a heavier gimbal reduce flight time?
Yes, and by more than its weight suggests, because holding it steady costs current on its own.
Why is my footage shaky even with a gimbal?
Usually the gimbal motors are undersized for the payload mass. They cannot hold the loop against wind and yaw.
Do I need a thermal camera for roof surveys?
For moisture mapping, yes. Thermal contrast shows what visible imagery cannot.
Tell us what the inspection has to prove and how close the aircraft can safely get, and we will match the gimbal, sensor and motors around it. The range is on our Skydroid accessories page, with the aircraft view in our thermal inspection guide.
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