The presence of fog density on a completed radiograph can arise from various factors. It may occur when the darkroom lacks lightproof conditions, when film holders exhibit cracks, when the power of the light bulb is excessively high, when the safelight filter is cracked, when an incorrect safelight series is employed, when the film is exposed for an extended duration to the safelight filter, or when the distance to the safelight is too short. Additionally, there are numerous other minor causes that can contribute to this issue.