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Loss of light:
Beside the target, the PRO35 Image converter has also other optical elements. An explicit
description would go beyond the scope of this manual. Therefore there should only be named
the main components:
Safety glass in front of the “target” (avoids permeation of dirt particles into the Image
Converter
Target glass – see above. This is at the same time the image plane (white engraving on
the body)
Prism block: Makes an optical adjustment of the image position possible (side-inverted
projection of the lens on the target). Therefore also old cameras can be used unlimited
with the Image Converter – the image is always projected correctly.
Adjustment lenses and second iris diaphragm: the rear part of the converter includes an
intermediate lens which scales down the 35 mm image projected on the target to the size
of the camera’s CCD (2/3" or 1/2") and corrects the light beam for the three focal planes
(red, green and blue) of the video cameras. Apart from this the intermediate lens includes
the back focus adjustment ring (see chapter above) and the second iris diaphragm (see
chapter above)
1.
2.
3.
4.
Naturally lenses NEVER work without loss of light. Also the optical system inside the three-
chip camera (prism) is often limited to maximum F1.4. Approximately 1 aperture is lost be-
cause of the projection of the picture onto the target glass and the other optical components.
The maximum aperture of the lens used has to be considered as well. Therefore check BE-
FORE shooting the loss of light resulting from your precise confi guration of lens and camera.
