Final Project, THE LENSE AND MAGNIFICATION for those filming with cameras instead of their phones

 

The Lens and Magnification

These terms from Module 6 have to do with the camera lens and magnification.

The focal length relates to the magnification of the image: how much "zooming power" is available in a specific lens. It is measured in millimeters. Different lenses have different focal lengths.

The standard focal length shows what you would see through one human eye. The focal length is 50mm and is suitable for a mid shot. If you put a 50mm lens up to each eye, you would see exactly the same way as if you were not looking through the lenses.

A wide focal length is 35 mm or less. You capture more visual information than the standard lens. It is a focal length that fits more of a scene into a frame. With a wide angle, you can make the subject you are focusing on look very large in comparison to the background. As your focal length increases, you start to see what is called background compression. The subject can stay the same size in your frame, while the background becomes compressed and alters your perspective.

A telephoto or zoom lens allows for the field of view to be adjusted, like a telescope. Focal length is often 70mm on up to 1700mm. These lenses are useful for a shot that demands a close-up of the subject, but needs to be shot from far away. It is very effective in creating a shot in which you really want to single the subject out.

The aperture is an inner element in a camera lens. It is what allows you to control focus by manipulating the physical size of the hole within the aperture. If the hole gets bigger, more light comes in. The hole gets smaller or bigger by moving the f-stopcontrol, visible on the outer part of the lens itself. This is how you create depth of field.

Depth of field is simply the area of your film frame that is in focus, sometimes referred to as the zone of sharpness.

A shallow depth of field is used frequently in filmmaking because it allows you to focus on something in the screen as part of your storytelling. That subject is the only thing in focus.

A deep or wide depth of field is used to show everything in the scene in focus for detail.

Rack focus is a creative technique where focus is deliberately changed within a shot. By modifying focus in a static shot, you will move the viewer's attention from one part of the film frame to another.

Zoom is magnification instead of movement. You are not changing the three-dimensional relationship of the surroundings to a character. The character gets larger in the frame, but the surrounding world stays basically the same.

A dolly zoom is a hybrid movement that happens when you combine a physical dolly move with a zoom magnification.