Classification of lenses according to Focal Length, Image Format, Characteristics, Utilizations

Name of the lens	Focal length 35mm equivalent	Image Angle	Characteristics	Utilizations
Short focal length lens or WIDE-ANGLE lens	21mm	90°	Wide image angle. Large depth-of-field and luminosity.	General plans and close objects that need a wide image angle and a large depth-of-field. It gives exaggerated perspective effects. Not good for portraits.
Medium focal length lens	35mm	63°	Normal image angle, with a perspective similar to that of a human eye	Used for taking photos in narrow places, where the distance between the subject and the camera is small.
Normal focal length lens	50mm	45°	Focal length close to the image diagonal.	Normal images and any kind of middle plans. Less obvious changes of perspective. Clear images on the entire cliché surface.
Telephoto lens	85-135mm	28-18°	Small image angle. Low luminosity.	Taking photos from the distance, close-ups. Architectural elements and corners of nature.
Super-telephoto lens	300mm	8°	Small angle of the field of vision: luminosity decreases.	Landscape photos, with details at large distances, players on sports fields, animals, birds etc. It brings distances closer.