Noise affects all captured images, regardless of the quality of the image sensor. One of the major contributors to image noise is heat within the sensor, where variations in thermally generated currents results in a fluctuation of measured pixel values. These fluctuations can severely impact on the robustness of applications that process the resultant image. To help better understand the effect that temperature has on image noise, we measured the illumination-independent (base-line) noise characteristics of 4 different industrial cameras and tracked their noise-performance from 21°C to 55°C. Results show that camera noise is highly temperature dependent, varies significantly between camera models, and can have unexpected characteristics.