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Film - Digital

What is angle of view?

Angle of view is perhaps an easier way of understanding focal length of a lens. This angle is formed by imaginary lines from the Centre of the lens - by locating the diagonally opposite corners of the film format, or CCD sensor used and projecting outwards to the diagonally opposite corners of the scene projected onto the recording medium. While the angle of view is hypothetical - it gives an relative indication how much of the scene will be included for each focal length lens. This angle becomes smaller as the focal length increases ( telephoto lens) and larger as the focal length decreases (wide angle lens).

 

With a 35 mm camera: 

Focal Length  Angle of View
50 mm standard lens 46degrees
20 mm wide angle 94 degrees
28 mm wide angle 74 degrees
35mm wide angle  62 degrees
85 mm small telephoto 28 degrees 30'
135 mm small telephoto 18 degrees
300 mm medium telephoto 12degrees 20' 
500 mm telephoto 5 degrees
600 mm telephoto 4 Degrees 10'
800 mm large telephoto 3 degrees

 

Move over image to see roll over

In practical terms we simply look through the lens and relate the scene in the viewfinder - if we have a zoom lens we zoom from one focal length to the next and the angle of view changes with this.

 

The angle of view is linked to perspective, as we alter the angle the perpetive alters, which means that the scale relaionship of objects within the scene alter.

 

For this image of the Last River Song project I used am  20mm - wide angle lens on a 35mm film camera. This had aan angle of view of 94 degrees.

This allowed me to include small objects like drops of water in the foreground while relating them the the wider environment. Because the sid angle lens covers a wider area you don't need to hold the camera quite as still. When used with a small aperture it also allowed a great depth of field with little camera shake. With this example - notice how using a wide angle lens eventuates the perspective - the camera viewpoint looking down the river augments this also.

However with this image from the Last Rivers Song, I used a 135mm lens on a 135mm camera. This had an angle of view of 18 degrees.

 

 

Because the film I was using was very slow - 3 ISO - this required a tripod to hold the camera steady. With this example the camera is positioned looking across the river to a small section in the centre.

See Shutter speed

 

 

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