Influence of infrared camera resolution and operator reproducibility in the assessment of skin temperature of the hands

Thermal cameras with varying resolutions are commonly used in scientific research, yet the impact of camera specifications and operator variability on temperature analysis remains unclear. This study evaluates the reproducibility of three FLIR thermal cameras with different resolutions (A655SC, E60, One Pro) and the influence of two practitioners on temperature measurements across 20 small regions of interest (ROIs) on the hand. A total of 126 thermograms were collected, resulting in 840 ROIs per camera. Reproducibility was assessed using intraclass correlation coefficients (ICC) and Bland-Altman plots. The A655SC and E60 demonstrated excellent reproducibility (ICC 0.961–0.998), while the One Pro showed lower agreement (ICC 0.154–0.831). Using the A655SC as the reference due to its higher resolution, the E60 underestimated skin temperature by -0.19 ± 0.55 °C, and the One Pro by -1.3 ± 3.4 °C. Despite differences in technical specifications, the A655SC and E60 provided comparable accuracy and reliability. In contrast, the One Pro's lower resolution resulted in less consistent measurements and a greater underestimation of temperature. Operator influence was minimal across all devices. These findings highlight the importance of camera resolution in thermographic assessments and support the use of higher-resolution models for improved measurement reliability.