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Camera Operation The Camera and controls Most cameras are fitted with a zoom lens; operated by a short handle attached to a ring around the lens barrel. Many cameras also have a "power zoom" operated by rocker switch in the hand grip. The zoom control is used to adjust the image size: it varies the effect of the lens from wide angle to close-up. The wide angle end of the lens will make the subject appear small and most distant, while the telephoto end will make the subject appear large and close. When possible: all focusing should be carried out with the zoom lens at full telephoto (close-up); then zoom back and frame the shot. The camera will have the following controls: power on/off, camera record, playback, tape eject and a button on the hand-grip to stop and start recording. Camera Movements PAN (from the word panorama) is to rotate the camera to left or right. TILT means to rotate the camera vertically. Always make these actions slowly except when following action, and always smoothly. The Tripod The tripod is a three legged support for the camera and is used to obtain steady shots; it is fitted with a fluid head that allows the camera to be smoothly panned and tilted. A handle is fitted to the head for the purpose of panning and tilting. There is always a certain amount of picture shake when shooting without a tripod. The Viewfinder The viewfinder is usually a small black and white or colour monitor with a magnifier and a rubber eye-cup attached. Usually there is a red lamp or other recording indicator that can be seen in the viewfinder. When not using the camera, make sure that the sun cannot shine through the magnifier as the heat will damage the viewfinder. ©2003 Ron H Bannister
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The Zoom Lens and Depth of Field A zoom lens is a lens that can be varied from a wide angle lens, through to a standard lens to a telephoto lens. Let us look first at the telephoto lens. this is like a telescope because it brings the subject closer or makes it appear to be larger, however it does not have a great depth of field; that is to say that there is only a very small area in front of and behind the subject focused on, that will actually appear to be in sharp focus. The wide angle lens makes the subject appear smaller or further away, and has a much greater depth of field; a larger area in front of and behind the subject appearing to be in sharp focus. If the lens is set at the full tele’ end of the zoom and focused at this narrow depth of field the image will stay sharp while the lens is zoomed back to wide angle. However with the lens set at the wide angle end, there is such great depth of field that it is impossible to accurately focus on the subject; Focusing slightly in front of the subject, or slightly behind it, would give an equally sharp image. If you have a lens set at the wide end, or even somewhere in between, and focus until the image appears sharp, you do not know whether you have focused on the subject, or in front of or behind it. This does not matter so long as you do not zoom in, because the picture will appear sharp. If the point of focus is actually behind the subject; when the lens zooms in the subject will become soft and some object in the background will come into focus. Likewise if the if the actual point of focus is slightly in front of the subject, zooming in will cause the subject will loose focus and some object in the foreground will become sharp. This is why it is always necessary to focus at the telephoto end of the zoom lens. ©2003 Ron H.Bannister Auckland NZ
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