When sourcing drone thermal cameras, the most critical specification is the Thermal Resolution (e.g., 640x512 is the industry standard for professional inspections). You must also evaluate the Thermal Sensitivity (NETD); a lower value (e.g., <50mk) indicates better ability to distinguish small temperature differences. Additionally, check the Frame Rate (30Hz or higher is preferred for smooth aerial footage) and the Lens Focal Length, which determines the Field of View (FOV) and the distance from which you can safely operate.