User`s guide

INDEX
52
This option is used with flatbed scanners to specify the size of the reflective media
you're scanning.
If set to "Auto", the full size of the flatbed will be previewed and the location and size of
the media automatically determined.
If a specific size is chosen, no preview is necessary when you press the Scan button.
This will save a significant amount of time.
Basic Option: This option is displayed when using reflective media (i.e. paper).
Input | Bits per pixel
This option specifies how many bits per pixel are read from the scanner. The more bits
that are read, the higher quality the image, but the slower the transfer speed at full
resolution. If you specify a value that the scanner isn't capable of, the closest valid
option is used instead.
Scanning at 24-bit resolution can add gaps to the final image histogram (compared to
48-bit resolution), but it can also speed up scanning with some scanners and often the
end result is virtually indistinguishable from 48-bit scans.
If this option is set to "Auto", the Input | Media (p. 50)option controls the number of bits
per pixel and samples per pixel used in a scan.
Advanced Option: This option is always displayed.
Input | Make gray from
This option specifies how to make the gray color from the scanner's red, green, blue
and infrared sensors.
The default, "Auto", either uses the scanner hardware to convert from the color CCD to
gray, or converts in VueScan, mostly from the green channel.
Otherwise, the gray color is taken from either the red, green, blue or infrared channels.
Using the red or infrared channel can be useful when scanning older, degraded
black/white negatives that are silver based.
Advanced Option: This option is displayed when scanning with 8-bit or 16-bit gray.
Input | B/W threshold
On some scanners, this option is used to control the threshold between black pixels and
white pixels, when scanning text or scanning at 1 bit per pixel.
The value of 128 works with most printed text, but if the text is light, you might need to
increase this to 200 or more.
A value of zero disables 1 bit per pixel scanning and uses 8 bits per pixel instead (with
the Color | Threshold (p. 74) option instead, allowing changing this option without
re-scanning).