Optical systems that emit radiation between the visible and near-infrared wavelength region pose a potential hazard to human vision as the radiation is imaged on the retina. The radiation interacts with the retinal tissue in a photomechanical, photothermal, and photochemical manner that can result in irreversible injuries. To ensure an eye safe system, it is important to correctly apply the laser safety standard IEC 60825-1:2014 or the lamp safety standard IEC 62471:2006. We aim to provide a general calculation procedure for both coherent and incoherent sources, which are compliant with the respective safety standards. An air-equivalent eye model generates retinal images. Two software-based calculation methods are introduced, which are referred to as image analysis. The first method calculates the angular subtense of the apparent source needed for photomechanical and photothermal limits. The second method applies to photochemical limits. Using exemplary optical systems, the image analysis is investigated. The proposed image analysis gives guidance for missing aspects in the standards and reduces ambiguity and complexity. The proposed method can be used for eye safety evaluations since it follows the concept of the safety standards with conservative approaches.