In keeping with this goal, the photographer must take care not to disturb the scene prior to taking photographs. Numerous photographs should be taken in order to ensure that all relevant aspects of the scene have been recorded. The crime scene must be photographed from long-, medium-, and close-range vantage points. Each stage of the commission of the crime must be treated and photographed separately. Prosecutors must be able to use photographs not only to record conditions, but to reproduce events. Photographers must remember that various range camera locations help to establish different points of view. Utmost effort must be directed toward the use of measurement scales when photographing elements of the crime scene for size and distance relationships. Photographs can generally be categorized as those focusing on the crime location, nature of the crime, results of the crime, physical crime scene evidence, and follow-up activity not directly occurring at the immediate scene. A photographic log should be maintained, recording the identity of the photographer, date and time, specific location of crime, orientation and description of photographic scene, type of camera and film, light source, distance from camera to subject, environmental conditions, focal length of lens, shutter speed, and lens aperture. Photographs will generally meet criteria for admissibility as evidence if they are accurate representations, free of distortion, material and relevant, and unbiased.