Nikon COOLSCAN V ED, Manual

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VRA53801-R.3609.A
- M7 ･ -
LS-50
2.6 Prescan
With Pitch 14 (corresponding to 286dpi) and Averaging being ON (8-pixel average in the main
scanning direction), total range of film is scanned and the host computer analyzes, etc histogram
(pixel distribution per brightness) targeting the following data.
MA-21
：
Posi: 25.1mm×36.8mm Nega: 18.7mm×29.0mm
FH-3 (with MA-21)
：
Posi: 25.1mm×35.1mm Nega: 18.7mm×29.0mm
SA-21
：
Posi: 25.1mm×34.5mm Nega: 18.7mm×29.0mm
IA-20(S)
：
Posi: 18.6mm×28.4mm Nega: 13.4mm×22.3mm
In case the maximum value is less than one half of the full-scale value, prescan should be performed
again by changing the exposure time so that the value falls in this range.
(Host processing)
Based on the result of pre-scanning, conditions for exposure are set for final-scan.
Regarding nega-films processing, histogram is created per color based on the prescan image, and the
max. and min. values of each color are calculated.
According to these values, min. and max. light exposure for each color are calculated, referring to
specified nega-characteristic performance curve. By adjusting so that the max. value of the max.
exposure for each RGB color become 16383, LUT is created based on the characteristic curve,
which describs the max. value of the max. exposure and min. value of the min. exposure of each
color.
Regarding posi-films processing, the color is decided of the max. value of pixels among RGB, and
the exposure time of RGB is multiplied by uniform scaling factor so that the max. value of the color
becomes 16383.
2.7 Nega-film base scanning
When SA-21 or FH-3 (with MA21) or IA-20(S) are used for nega-films, the base part of films
(between frames, etc) is scanned to get the information on density of films. This density information
is used for image output of nega-films.
2.8 Preview
The digital compensation is made based on the presan data, and preview image is created to
displayed. (Host processing)
After the 2nd preview, the image is got by adjusting exposure and performing rescan.
2.9 Final scan
The final scan is performed in the designated scanning range and under the scanning conditions.
LED lights up per 1 line; the CCD is driven and the data is written in the buffer; data is transmitted
to PC; the scan block unit is moved. The image data transmission is made in parallel with other
processing. The movement of the scan block unit is made while each LED for R, G, B, and I is NOT
lighting.