About the Author: This guide was synthesized from ISO standards, manufacturer technical notes, and field experience from Level II and III thermographers. For specific applications involving medical, aerospace, or nuclear safety, consult a certified thermography engineer.
Infrared thermography is a non-contact method used to measure surface temperatures by detecting infrared radiation. While it is widely used for industrial diagnostics, medical screening, and environmental monitoring, its accuracy is often limited by complex physical interactions between the object, its surroundings, and the atmosphere. Quantitative measurement requires a deep understanding of the uncertainty budget infrared thermography errors and uncertainties pdf
| Component | Uncertainty (±°C) | | :--- | :--- | | Emissivity (tape applied, ε=0.96±0.01) | 0.8 | | Reflected temperature (estimated ±2°C) | 1.2 | | Atmospheric correction (distance 2m, 50% RH) | 0.5 | | Detector noise (NUC performed) | 0.3 | | Geometry/angle (60° incidence) | 0.7 | | | ≈ ±1.7°C | About the Author: This guide was synthesized from
Water vapor and carbon dioxide in the optical path absorb infrared radiation—especially in the long-wave (8–14 µm) and mid-wave (3–5 µm) bands. While it is widely used for industrial diagnostics,
Non-uniformity correction (NUC) routines are necessary but imperfect. After a camera warms up or during rapid temperature shifts, residual non-uniformity mimics real thermal patterns.
Out-of-focus images spread energy across multiple pixels, reducing apparent temperature and blurring hot spots. Always use manual focus, even if the camera has autofocus.
An out-of-focus image is not just blurry; it is radiometrically incorrect.