Focus - Nikon Coolscan Bedienungsanleitung

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4-4 Focus
There may be times when it is necessary to adjust the
focus control in order to achieve maximum scann ing
performance. Focus control becomes more significant
when a high resolution scan is taken . High resolution
typically ranges from Pitch=1 to Pitch=2 scans .
Focus is affected by the position of the film with respect
to the optics in the scanner. The most common
parameter that can cause focus problems is the
thickness of the film mount. Fortunately, the scanner
utilizes a self-adjusting focus mechanism. This
mechanism automatically centers the film in the center
of the focal region regardless of the thickness of the
slide mount.
It should be noted that the focus control of the scanner
cannot be used to sharpen unfocused film . These are
some software processing techniques that can be used
to help sharpen unfocused film .
The following is a list of things that can affect focus .
Thickness of the slide mount
There is a wide variety of slide mounts popularly used
today. The thickness of these mounts affects where the
film will be positioned within the slide mount and
consequently within the scanner. This scanner utilizes a
self-adjusting focus mechanism . This mechanism
automatically centers the film in the center of the focal
region regardless of the thickness of the sl ide mount.
The film type
Many film types are used today . The film material , film
thickness , dyes and emulsions used on the film can
affect how light passes through the film and
consequently affects the focus .