The maintenance of large
format colour scanners can sometimes be difficult to grasp particularly if
you have not used a large format scanner before. The good news is that the majority of image difficulties
with a large format scanner can be avoided by simple and regular scanner maintenance.
The Gx 42 contains 5 cameras and the Gx 25 three. If the copy or
scan file shows some colour differences at intervals of a 1/5 or
a 1/3 across the scanner then it will most probably be due to the
following:
Reason#1: The temperature inside the scanner has not stabilised properly because the device has not been allowed to warm up. Remedy: Leave the scanner switched on for 1 hour and then re-normalise with clean white paper using the Gx Utilities program.
Reason#2: The scanner is already warm but was last normalised for a
different room temperature (different by > +/- 5
degrees C) Remedy: Use Gx Utilities to normalise the scanner at the working room temperature.
NOTE:
These actions are considered part of routine scanner maintenance.
For black and white scanning they are not so important.
camera to camera stitch
The
Gx 42 and Gx 25 contain multiple cameras. If the copy or scan file
show problems with thin lines or edges of objects at intervals of a 1/5 or a 1/3 across
the scanner then it will most probably be due to a camera stitch issue:
FRONT/ BACK
If horizontal lines, for example the rim of the glass (see picture to
right) is displaced in the direction of paper movement this will
indicate a Front/ Back stitch error.
There may, or may not be a Left/Right error at this camera intersection
as these are not so easy to spot unless there is a diagonal line
discontinuity or distortion of an object of recognisable shape e.g. a
circle on the original document at this point.
Reason: The scanner may have been handled roughly or subjected to
intense temperature changes recently. However, this effect is hardly
ever serious and can be repaired with some simple maintenance
(electronic) using the Stitch Target included with the scanner. Remedy:
Use Gx Utilities to re-stitch the scanner at this room temperature
after the unit has been switched on for 1 hour This process will
take about 3 minutes.
NOTE:
The maintenance procedure described above will repair stitch problems
caused by camera misalignment. Stitch irregularities can also be caused
by irregularities in the document or the passage of the document
through the scanner.
Cx 40 scanners require re-stitching in a similar way using the Cx
Utilities program. For stitch maintenance to be most effective
Cx 40 scanners should also be allowed to adjust to room temperature
before carrying out routine maintenance.
If diagonal lines have been broken, shapes have been distorted
(overlapping left right) or picture data is repeated (cameras moved
apart) but horizontal data is not affected, this indicates that
the scanner needs left/ right stitch maintenance.
Reason: As above, although maintenance for this type of stitch effect
is more rare. See the example right (cameras too far apart) Remedy:
Use Gx Utilities to re-stitch the scanner at this room temperature
after the unit has been switched on for 1 hour This process will take
about 3 minutes.
FALSE DIAGNOSES
For Gx series CCD scanners 'paper lifting optical effects' caused by heavy creasing or folds can be often be confused with a permanent LEFT/ RIGHT
camera problem. Check the maintenance level of the scanner by
scanning the flat stitch target BEFORE re-stitching the scanner. Remedy: flatten the document and re-copy or scan For Cx 40 scanners the
majority of false alarm stitch diagnoses arise from evidence of FRONT/
BACK stitch effects in the copy or scan. In this model of scanner
there are two main causes:
Reason#1: Paper lifting, heavy creasing or folds can cause irregular paper velocity between sensor lines Remedy: flatten the document and re-copy or scan
Reason#2: Thick, heavy documents suddenly meeting rear roller can cause unexpected document speed reduction and irregular paper velocity between sensor lines Remedy: rescan the document, rotate the document and/ or slow the copy speed down
NOTE: For more detailed information on camera stitching please refer to the service manual for the relevant scanner model.
grey or off-white backgrounds in colour or greyscale copies
Explanation: White point collects all shades of grey whiter than the white point threshold and replaces them with white.
AVOID using the Brightness slider as this will whiten the background but also affect all other colours in the copy.
The
background of a technical drawing when copied as a greyscale or colour
document may appear slightly grey (plan copier output) or off-white (newspapers). In extreme cases there
may be varying levels of grey corresponding to the separate cameras (Gx
Series) or CIS arrays (Cx 40) making up the scanner.
Reason#1: The scanner is not fully warmed up or the scanner was last normalised at a very different room temperature. Remedy:
Allow 1 hour then re-normalise using the normalisation target supplied and the scanner Utilities program.
Reason#2:
The standard normalisation target supplied with the scanner or paper
used to normalise the scanner is whiter than the background of the
document being copied or scanned. Remedy:
Allow 1 hour (if recently switched on) and then re-normalise using paper closer in whiteness to the
document being copied using the Utilities program
OR use the white point slider in
CopySmart to whiten the background. Do not use brightness as this will affect all colours in the copy. Reason#3: The document uses a non-white paper. Remedy: Copy the document in black and white mode if colours are non-essential.
See the Tutorial - black & white copying
colour performance
CopySmart
uses ICC profiling for the scanner and printer connected through the
LAB colour connection space at the centre of its colour management
process. If the colour performance is not satisfactory it may be
necessary to change to a higher specification media. Matt coated
papers generally give good results for CAD and general technical work
but photo gloss or satin gloss high resolution media is recommended for
the very best results.
Better colour accuracy can be obtained by
using the spectrophotometer route instead of the scanner to calibrate
the system (available 2007).
speed issues
CopySmart
will usually start printing the copy through the Windows spooler as
soon as the computer has processed enough data - normally
after about 10 seconds.
For best copy performance enable the 'Spool print documents so program finishes faster' and 'Start printing immediately' radio buttons.
Using 'Print directly to the printer' will prevent CopySmart from previewing any further documents while the current original is still being copied.
copy slightly larger or smaller than the original
CopySmart
unlike many standard Windows printers is specifically designed to
preserve the size of the original. If the size of the copy is
smaller or larger than the original in the paper direction or across
the scan width this could indicate the scanner may need attention by a
qualified service technician.
Correcting the size of the copy by un-checking the Maintain Aspect Ratio box and retyping the correct length or width or both for a second copy may be successful as a temporary workaround.
2
Troubleshooting CopySmart
CopySmart
copying software relies on the existence of a fully installed
Windows driver ON THE SCANNER COMPUTER to use as a network port
connection. CopySmart users are recommended to use the internal
printer drivers although the product can be configured with an internal
connection to regular Windows printer drivers. Common
problems encountered with CopySmart are as
follows:
CMYK
drivers usually give better colour performance and require use of the
IT8 target and production and scanning of printer targets. Full
CMYK colour calibration is carried out for each media used in the
printer and usually takes about 15 minutes. RGB drivers rely on the
colour tables used in the printer and are much faster to get working
because no ICC profiling is required. See Copying Tips for more explanation of the different types of RGB driver.
copies taking too long to print
Black
and white draft copies are often not required at such high quality as
photo glossy copies of maps and detailed originals. Change the
COPY resolution to 200 dpi using the COPY i button. Also make
sure that the quality setting in the media you are using is suitable
and that you have selected the correct media (which contains that
setting).
changing copy print quality
Copy
quality changes are made first by increasing the scanner COPY resolution
but ALSO controlled by the quality setting selected in the MEDIA when
the profile was made (during the 'Add a new printer' step). We
recommend when creating the profile for a media, a clue to the quality
setting is recorded in the Paper name e.g. PLAIN PAPER - DRAFT
discoloured areas to side of copy
These
are produced when the scanner copies the roller around the sides of the
original. This can be avoided by Previewing the original and
manually cropping to the edge of paper OR by switching on Auto Size.
Preview not working with long originals
Preview
is normally restricted to documents whose LENGTH is not more than 3x
their WIDTH. To preview long documents change the value in the
.cwi file from 3 to a higher number.
blueprint copies are not being copied cleanly
For
efficient semi-automatic cleanup of variable background select the
Advanced Black & White Preset from the Drawings Document Type
colour match to original is not close enough
If
the scanner is at a stable running temperature, normalised
and profiles have been made for the scanner and media in use, the
value of the Tint Removal
setting should be changed. Making the value higher (default is
4) will lighten colours but can reduce the detail in the lighter
coloured areas of the copy. If this does not work try rebuilding
the printer profile with a different ink level.
my printer is not on the printers list
Printers are being added all the time to CopySmart. Please contact your dealer or distributor for details
lines in the copy not in the original
This
is most probably due to dirt on the glass OR DIRT ON THE GLASS WHEN THE
SCANNER WAS NORMALISED. Clean the glass with a lint-free cloth
and suitable good quality glass cleaner and then re-normalise using the
Utilities program for your scanner.
