# Focal Length and Photography (Bard) ## What can tell me about focal lengths in regards to digital photography? edit  Focal length is one of the most important concepts in photography. It is the distance between the lens and the image sensor when the subject is in focus. The focal length of a lens is measured in millimeters (mm). The focal length of a lens affects the field of view, depth of field, and magnification. - Field of view is the amount of the scene that is captured by the camera. A wide-angle lens has a wider field of view than a telephoto lens. - Depth of field is the range of distance in front of and behind the subject that is in focus. A wide-angle lens has a shallower depth of field than a telephoto lens. - Magnification is the enlargement of the image. A telephoto lens magnifies the image more than a wide-angle lens. The focal length of a lens can be changed by zooming in or out. When you zoom in, the focal length increases and the field of view decreases. When you zoom out, the focal length decreases and the field of view increases. The focal length of a lens is one of the most important factors to consider when choosing a lens for photography. The focal length that you need will depend on the type of photography that you want to do. For example, if you want to take landscape photos, you will need a wide-angle lens with a short focal length. If you want to take close-up photos, you will need a telephoto lens with a long focal length. The focal length of a lens also affects the perspective of your photos. A wide-angle lens will make objects appear smaller and closer together, while a telephoto lens will make objects appear larger and further apart. The focal length of a lens is a powerful tool that can be used to create stunning photos. By understanding the relationship between focal length and the other factors that affect photography, you can take your photography to the next level.