sane-canon(5)							File Formats Manual						     sane-canon(5)

NAME

       sane-canon - SANE backend for Canon SCSI scanners

DESCRIPTION

       The  sane-canon	library  implements  a SANE (Scanner Access Now Easy) backend that provides access to the following Canon flatbed and film
       scanners:

	      CanoScan 300
	      CanoScan 600
	      CanoScan FB620S
	      CanoScan FS2700F
	      CanoScan FS2710

       No parallel port and USB scanners are supported and there are no plans to support them in the future.

       IMPORTANT: this is alpha code. Don't expect this to work correctly. Many functions are missing, others contain errors. In some cases,  your
       computer might even hang. It cannot be excluded (although I consider it extremely unprobable) that your scanner will be damaged.

       That  said,  TESTERS  ARE  WELCOME. Send your bug reports and comments to Manuel Panea <mpd@rzg.mpg.de>; for questions concerning the FB620
       contact Mitsuru Okaniwa <m-okaniwa@bea.hi-ho.ne.jp>, for the FS2710 Ulrich Deiters <ukd@xenon.pc.uni-koeln.de>.

TIPS (FS2700)
       Scanning either slides or negatives has been found to require rather large gamma corrections of about 2.2  to  2.4  (same  value  for  red,
       green, and blue). Also, for slides, using "Auto Exposure" helps a lot.

       The  "Auto  Exposure" function for slides makes the scanner do a first pass on the film to determine the Highlight and Shadow point values.
       The "Auto Focus" function triggers yet another pass to determine the focus value. After that, the real scanning pass takes place. The "Auto
       Exposure" function is not available for negatives yet.

       Even  with "Auto Focus" turned on, the scanned image is often a bit too blurred. Using the GIMP to do a "Filter->Enhance->Sharpen" at about
       40 to 60 improves the image considerably. It is likely that a sharpen filter will be included in a future version of this backend.

       The "native" scanner resolutions of the 2700F are the integer sub-multiples of 2720 dpi, i.e. 1360, 680, 340 and  170.  Scanning  at  other
       resolutions is possible, but there will be noticeably more jaggies in the image than when using one of the "native" resolutions.

TIPS (FS2710)
       Gamma  corrections  are	done  not by the scanner, but by the backend.  The scanner is always run in 12-bit mode. In "color" mode the image
       data are corrected for gamma, shadow point, etc., and then truncated to 8-bit intensities; the default gamma value is 2.5.  In  "raw"  mode
       the  image  data  are  exported without corrections as 16-bit intensities; this mode can be recommended if extensive adjustments have to be
       made to a picture (and if the frontend can handle 16-bit intensities).

       Negatives are handled by simple color inversion and may require manual removal of blue discoloration.

FILES

       /usr/lib/sane/libsane-canon.a
	      The static library implementing this backend.

       /usr/lib/sane/libsane-canon.so
	      The shared library implementing this backend (present on systems that support dynamic loading).

ENVIRONMENT

       SANE_DEBUG_CANON
	      If the library was compiled with debug support enabled, this environment variable controls the debug level for this backend.  Higher
	      debug levels increase the verbosity of the output.

	      Example: export SANE_DEBUG_CANON=4

SEE ALSO

       sane-scsi(5)
       http://www.rzg.mpg.de/~mpd/sane/
       doc/canon.install2700F.txt (installation of a CanoScan 2700F

AUTHOR

       Helmut Koeberle, Manuel Panea, and Markus Mertinat; FB620S support by Mitsuru Okaniwa; FS2710 support by Ulrich Deiters
       Man page by Henning Meier-Geinitz (mostly based on canon.README)

								    03 May 2001 						     sane-canon(5)