Not all thermal cameras are equal: why the camera makes or breaks the inspection
"I have a thermal camera too" — you hear that a lot. But between a smartphone thermal add-on and a Matrice 30T lies a world of difference. And it is exactly that difference which decides whether a defect is found or missed.
Why does this matter?
A thermal image is only as reliable as the sensor that makes it. Three properties decide everything: resolution (the number of measurement points), thermal sensitivity or NETD (the smallest temperature difference that rises above the noise) and optics (how much of the world lands on one pixel). Fall short on any one of the three and a small hotspot disappears into noise or blur — and you wrongly declare a faulty installation healthy.
How does this work in practice?
The radiometric sensor of a Matrice 30T combines a usable thermal resolution with a low NETD and sits on a stabilised gimbal, producing sharp, measurable images even from the air. A smartphone add-on has a far lower resolution, more noise, often no real radiometry and no stabilisation. The ratio between distance and target is crucial: a faulty cell must cover several pixels to be measured reliably. At distance, with a cheap camera, that cell falls within a single pixel and its heat is averaged with the cold surroundings.
Common mistakes
- Using a cheap camera at long range. Too few pixels on target makes every measurement unreliable.
- Ignoring NETD. High noise masks exactly the subtle differences that matter.
- No stabilisation. A shaky thermal image is not sharp enough to isolate a cell.
- "It's a thermal camera, isn't it." The brand or existence of a camera says nothing about measurement quality.
Why with a drone?
A professional drone sensor brings resolution, radiometry, stabilisation and reach together. You measure a full roof or array under equal conditions, at the right distance for enough pixels on target, and with an image sharp enough to isolate and measure individual defects — something a handheld camera from the ground rarely achieves.
Why Droneview?
Droneview flies the Matrice 30T and deliberately picks flight height and distance based on the target, so every module gets enough pixels. No cheap shortcut, but a measurement that holds.
Frequently asked questions
Can I inspect solar panels with a smartphone thermal camera?
For a quick close-up look perhaps, but not for a reliable inspection. The low resolution, higher noise and lack of stabilisation cause small defects to drop out at distance or from the air.
What does a thermal camera's NETD mean?
NETD (Noise Equivalent Temperature Difference) is the thermal sensitivity: the smallest temperature difference the camera can still tell apart from noise. A high NETD drowns subtle hotspots in noise.
How many pixels must a defect cover for a reliable measurement?
As a rule of thumb a defect should cover several pixels; with too few pixels on target the measurement averages the hot spot with its cooler surroundings and underestimates the temperature.
Why is resolution more important than it seems?
Resolution determines how many measurement points you have per module or roof plane. At too low a resolution you see a vague warm area but cannot isolate or measure an individual faulty cell.
Unsure about the quality of an earlier scan?
We inspect with a professional radiometric sensor at the right distance — measurable and reliable.
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