[sane-devel] Digital ICE support

[Jonathan Buzzard]

Note: please don't cc or reply directly.

andras at users.sourceforge.net said:
> Agreed. I think there should be a sanei_* library that allows the code
> to be used in frontends or meta-backends, whichever solution is best.
> (Just think of a network scanner that is accessed by a handheld device
> -- you don't want the IR cleaning to be done on the handheld.) 



> True. On the other hand, there isn't much room between the visible
> range (down to about 730nm as you say) and the longest wavelength that
> can be picked up by a CCD, so I think there isn't much variation
> between scanners there. 

Well your standard CCD goes up to around 1000nm, so that gives plenty
of room for choosing an IR wavelength.

The alternative might be to try UV cleaning, though I suspect that the
idea of illuminating precious negatives with UV might not be welcome.


> That's an interesting development, and certainly worth looking into.

See the URL below for more information. Personally I would just have
adjusted the relative position of the IR CCD line to account for it's
moved position due to chromatic aberration.

   http://www.canon.com/technology/detail/flatbedscanner/fare/index.html

In fact the more I think about that idea the more I like it. Why stop at
the IR line, have the positioning for all four lines set so that you can
use cheaper optics and not have to worry about the chromatic aberration.
Well you are worrying about it, but rather than spending money on
reducing it, you just use it to your advantage, as the RGBI elements
of the CCD in a line scanner cannot all be in the same position in
the first place. That is assuming you are not using Foveon(tm) style CCD
sensors of course.


JAB.

-- 
Jonathan A. Buzzard                 Email: jonathan (at) buzzard.me.uk
Northumberland, United Kingdom.       Tel: +44 1661-832195