Find a scene that has depth. From a fixed position, take a sequence of five or six shots at different focal lengths without changing your viewpoint. (You might like to use the specific focal lengths indicated on the lens barrel.)
Of these shots, the middle – 50mm – feels closest to how I perceive things, but not closest to my normal angle of vision, which is much wider. Zooming in does not change the relationships – enlarging the centre of the 18mm frame effectively produces the 200mm frame.
Select your longest focal length and compose a portrait shot fairly tightly within the frame in front of a background with depth. Take one photograph. Then walk towards your subject while zooming out to your shortest focal length. Take care to frame the subject in precisely the same way in the viewfinder and take a second shot. Compare the two images and make notes in your learning log.
The perspective distortion is clearly visible with elements from the grape vines appearing in the second shot which were absent in the first. Since the focal length has decreased, the depth of field has increased in the second short compared with the first.
Choose a subject in front of a background with depth. Select your shortest focal length and take a close low viewpoint, below your subject. Find a natural point of focus and take the shot.
The combination of a wide lens and low viewpoint causes extreme perspective distortion and adds drama to the shot.
Find a location with good light for a portrait shot. Place your subject some distance in front of a simple background and select a wide aperture together with a moderately long focal length such as 100mm on a 35mm full-frame camera (about 65mm on a cropped-frame camera). Take a viewpoint about one and a half metres from your subject, allowing you to compose a headshot comfortably within the frame. Focus on the eyes and take the shot.
The combination of a relatively long focal length and wide aperture make the background very blurred and serve to separate the subject nicely from the background.
Find a subject in front of a background with depth. Take a close viewpoint and zoom in; you’ll need to be aware of the minimum focusing distance of your lens. Focus on the subject and take a single shot. Then, without changing the focal length, set the focus to infinity and take a second shot.
The point of focus strongly attracts the eye – when this is in the foreground it seems more comfortable than when the foreground is out of focus.
Use a combination of wide apertures, long focal lengths and close viewpoints to take a number of photographs with shallow depth of field. (Remember that smaller f numbers mean wider apertures.) Try to compose the out-of-focus parts of the picture together with the main subject. Add one or two unedited sequences, together with relevant shooting data and an indication of your selects, to your learning log.
The long focal length and wide aperture create a small depth of field most noticeable in the middle shot where it is clear that there is a plane of sharp focus and only a small distance either side which is acceptably in focus.
Use a combination of small apertures and wide lens to take a number of photographs exploring deep depth of field. Because of the small apertures you’ll be working with slow shutter speeds and may need to use a tripod or rest the camera on a stable surface to prevent ‘camera shake’ at low ISOs. Add one or two unedited sequences, together with relevant shooting data and an indication of your selects, to your learning log.
The combination of a short focal length and relatively small aperture give a deep depth of field with seeming sharpness from the close foreground to infinity.