Depth of field | Infrared Photography |
Depth of field (D.O.F) is defined as the zone of sharpness before and behind the plane of focus. It depends on camera subject/distance, focal length of lens, aperture setting and distance the lens is focused at.
In addition to visual observation via the depth of field preview button (See page 66.), the D.O.F can be determined by using the depth of field scale on each lens. f/stop numbers appear on both the right and left side of the white index mark in the center of the scale. Simply read the figures which appear above the f/stop numbers on the distance scale of the lens. (see illustration below)
When the aperture is large (the subject depth is small)
When the aperture is small (the subject depth is large)
When taking photos using infrared film, the position at which the subject is in focus is slightly different from during normal photography. This is because the infrared rays have a longer wavelength and the image converges further back than normal. Use the procedure described below when taking photos using infrared film.
1.Set the focus as usual. Find the point on the distance scale matching the subject depth scale's central index.
2.Set the focus mode selector lever to "M" (manual focus mode). Turn the focusing ring clockwise and set the distance scale to the above infrared index.
*Use a red filter when taking photos using infrared film.
*Be sure to read the infrared film's usage instructions.
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