White Calibration For Reflectives - Hasselblad Flextight 646 User Manual

Hardware Reference - Flextight 646
22
Calibrating the Scanner

White Calibration for Reflectives

The Flextight scanner uses a white reference to make sure that all
elements in the scanner's CCD react consistently to light brightnesses.
The scanner has been calibrated from the factory, and the calibration
data is stored in the scanner's flash PROM.
As the scanner ages, the properties of the light tubes may change
slightly. Therefore, you must redo the white calibration every six months
or so and immediately after changing the light tubes.
Use procedure below to make White Calibration:
1.
2.
3.
4.
Find the white calibration sheet that came with your scanner. It is a
square white piece of paper (219 x 219 mm (8.6" x 8.6")).
If you have lost the white calibration sheet, then you can use a flat
(non-textured), perfectly white piece of paper of the same
dimensions.
If you have used the reflective holder before, make sure that there
are no finger prints or other marks on the plastic layer. Replace the
layer with a new one if necessary.
(Please note that the A4/letter-size reflective holder in not included
in the standard delivery).
Align the top edge of the sheet with the dotted line near the top of
the original holder (see Figure 8 opposite). Align each side of the
target with the edges of the original holder.
Select White Calibration from the Maintenance window. The
External White Calibration window appears.
User's Guide - Flextight 646