External (non-integrated) IR illumination can significantly enhance the performance of surveillance cameras in low-light conditions. By increasing contrast in the scene, it allows the camera to capture clearer images with more detail. Additionally, external IR illumination provides more flexibility in placement and coverage, ensuring that the entire area of interest is adequately illuminated. This can be particularly useful in large or irregularly shaped areas where integrated IR might not be sufficient. Axis documentation supports the use of external IR illuminators to improve image quality and scene visibility in low-light environments.