FOR-A VFC-1000, Руководство по эксплуатации

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6. Record Tips
In order to record high-speed phenomena without problems using a high-speed camera, it is
necessary to select recording speed, shutter speed, lens, and lighting equipment which are
appropriate for the speed of the subject.
6-1. Recording Rate and Shutter Speed
Recording rate: Generally, recording rate is decided by how many times a fast-moving
subject is to be recorded per second. A given fast-moving subject will require a faster
record speed when recorded in a narrow field of view (using a telephoto lens with a long
focal length) than when recorded in a wide field of view (using a wide-angle lens with a
short focal length). For example, if the subject is recorded with a x2 focal length lens, the
recording rate is doubled. Close-ups and microscope shots require a recording rate faster
than the actual speed.
Shutter speed: High-speed phenomena are recorded at higher recording rate. However, if
the subject moves a large amount within the record time for a single frame, the recorded
image will blur. Therefore, in order to record images with as little blurring as possible during
high-speed recording, a high-speed electronic shutter is used for short exposures during a
single frame intervals. As shutter speed increases, image sharpness increases, but the
illumination required on the subject also increases. Therefore, shutter speed is reduced
within the allowable blur range during still image playback. A general guideline is five times
the recording rate (e.g., for recording rate of 250f/s, the shutter speed would be
approximately 1/250
×
5 = 1/1250 second).