Focal Length Technique Post

Definition- The focal length of the lens is the distance between the lens and the image sensor when the subject is in focus, usually stated in millimeters (e.g., 28 mm, 50 mm, or 100 mm). In the case of zoom lenses, both the minimum and maximum focal lengths are stated, for example 18–55 mm.

Field of view is determined by the angle of view from the lens out to the scene and can be measured horizontally or vertically.

Larger sensors or films have wider FOV's and can capture more of the scene.

In 35mm photography, lenses with a focal length of 50mm are called "normal" because they work without reducing magnifying and creates images the way we see the scene with our naked eyes (same picture angle of 46 degrees).

Wide angle lenses (short focal length) capture more - wide picture angle.

Telephoto lenses (long focal length) narrow picture angle.