| 摘要 |
<p>A video transfer stand (12) generates a video signal from a front-illuminated image on a semi-transparent or translucent original (16), especially a photographic print. The video system, including the transfer stand (12) and a video display (26) connected to the stand, produces output video contrast as a function of the transfer characteristic (gamma) of the video system as it interacts with the contrast exhibited by the reflection density of the print. This interaction produces high contrast that blocks out details especially in shadow areas of the video display. Such undesirably high contrast is moderated-releasing shadow detail-by variably backlighting the print in the transfer stand by means of a backlight adjust circuit (42). The illumination from the rear illuminators (36a, 36b), which are adjusted in view of the display, produces inherently lower contrast than the reflected illumination and, in combination therewith, optimizes the video display contrast.</p> |
