December 14, 2007

4800x4800 dpi ... The eye of the ... Scanner

Not just because the MP610 (and also MP630, MP970...) can now scan at 4800 dpi under Linux … before any 'Doze driver propose it ...?

But simply consider this Pixma scanner: can we call it a scanner? Or rather an electronic microscope?

Cannot see a detail on a photograph? just scan it with your Pixma at 4800 dpi …
and you get about 50 x zoom magnification!

Just take a look at the rightmost image. Open, it. Guess a new carpet design? Nope, simply a detail of a classic French "Marianne" stamp (here, a full view at 600 dpi), as seen by the Pixma MP610, at 4800 dpi...

Scanning at 4800 dpi is not for everyday’s usage, but this is a nice feature to have for particular tasks.

Now, some simple orders of magnitude...
  • 4800 dpi means a resolution of 2.54 cm/4800 = 5.3 µm
  • this is ~1/1.000 of a millimeter, or 1/1.000.000 of a meter
  • and also simply… ~10000 times the atom size (1 Angström = 1E-10 meters) …

So ... Will future scanners be able to display … the paper sheet atoms?!

Nothing new, the same procedure as for previous version of this driver applies:

  • simply install the latest sane-backends library (either 1.0.20 or latest git development and follow the installation instructions given in this post.
  • Then, select in your frontend (Xsane, Kooka, …) a scan resolution of 75, 150, 300, 600, 1200, 2400, or 4800 dpi ... and start scanning...


Be very careful when scanning at such high dpi values, because you’ll get TREMENDLY HUGE ENORMOUS amount of data and file sizes!

You could fill up your entire disk space in one scan!

Watch carefully the frontend indications about file sizes, before clicking the scan button!

Note also that in case of very large images (like more than 20000 pixels width or height in Xsane...), a frontend crash might occur, due to the large image size...

Multi-page scanning using MP610 scanner buttons

Scanning several pages at a time is easily achieved with an ADF scanner, however, the MP610 does not have one.

A small command line utility included in libsane-pixma library, named “scan” , can manage the MP610 scan buttons, which greatly helps for scanning several pages.

But a graphic frontend, like Xsane, is more comfortable to achieve this. Multi-pages scanning feature has been added to latest versions of Xsane, as well as in other frontends (like gscan2pdf…), for scanning multi-pages documents with an ADF scanner.

Xsane can only perform ADF multi-pages for now, as said in Xsane documentation.
As the MP610 does not have an ADF, setting more than 1 page to scan in Xsane will simply produce … an I/O error ;-(

Fix proposed
Scanning multi-pages images, documents, projects, from various Sane frontends is now possible with the Sane library.
This fix should also work (but not confirmed) with other Pixma - non ADF - scanners too.
Install the latest Sane library as explained in this post.

Example with Xsane
When Xsane detects a MP610, a window (here on the right) gives access to several parameters. Note that this window can be activated from the main menu, "Window/Standard options".
  • Select the “Button-controlled scan (experimental)” option.
  • Set several pages to scan in Xsane main window, and the output document format,
  • Click Xsane “scan" button. The MP610 does _not_ start scanning yet.
  • Now go in front of the MP610, and select the scanner mode using MP610 rotating wheel. Choose saving documents to a folder.
  • Place the first page to scan, and press the MP610 "color" button. The first page is scanned, then scanner pauses.
  • Place the second page and again, press color button, and so on …

Scanning can be stopped at anytime by pressing the "B/W" button (note you will receive an I/O error in your Frontend ; this is currently working as designed, altough a bit clumsy. This behavior could be easily changed).

When finished, go back to your computer: the scanned pages will be waiting in Xsane…

Isn't time to archive on DVD, those old piles of invoices, papers …that fill your drawers…?!