FOR-A VFC-1000, Operation Manual

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6-2. Lens Selection
Camera sensitivity is insufficient for high-speed recording. Therefore, select the largest
aperture lens possible.
Lens mount: Use a C mount. A CS mount cannot be used. A Nikon F mount lens (for 35
mm photography lens, bayonet mount) may be used with an F-C adaptor.
Lens: Select a megapixel-compatible lens with high resolution, low distortion and high
performance. Use CCD size of 2/3-inch or 1/2-inch.
Close-up shots: If the object distance is shorter than the minimum object distance shown in
the lens catalog, adjust camera focusing by inserting close-up rings between the camera
and the lens. Close-up rings are commercially available in the following sizes. Use a
combination of these sizes to make the adjustment.
Ring thicknesses: 0.5mm, 1.0mm, 5mm, 10mm, 20mm, 40mm
For much closer shots, a special lens with a high optical magnification (capable of
displaying a 10-mm or smaller subject over the entire monitor screen) is required, but
aperture of such lens is small.
Field of view of VFC-1000: The effective recording area of the VFC-1000’s CCD is reduced
as recording rate is increased, and the record field of view for the given lens is also
reduced in size. For example, in order to record a subject which has a given size at 250 f/s
so that it fills up the entire monitor screen at 1000 f/s, the object distance is half.
Fig. 6-1
250f/s field
1000f/s field
Half the size at 250f/s