[sane-devel] scanning negatives

[John Coppens]

On Sun, 24 Sep 2006 00:09:02 -0700
Jamie Morken <jmorken at shaw.ca> wrote:

> I've been trying to figure out the best light source
> to use for scanning negatives, I've tried flourescent, incandescent, a
> flashlight, a white lightbox etc but all of the scans look horrible 
> so far, with only green colour once I invert them.

Hi Jamie.

This is a very scanner-specific solution, but it worked for me:

I had hundreds of slides I wanted to scan, before they were completely
discolored or ruined by the fungus I detected on some of them. I first
tried several light sources, but quickly realized that 1) the light
source must be very precisely positioned to be of use, 2) the spectrum
of the source should be the same as the one in the scanner, and 3) it
should be fed with DC or high frequency, as AC sources cause lines.

I made a 'tent'-like structure with two cheap mirrors (5 by 10cm) at 45
degrees to reflect the light of the scanner back down, experimented a
little tilting the structure till the light went correctly back. 

Scanned all the slides with quite good results! 

This won't work with the more modern LED-illuminated scanners, and, I
understand there are some fluorescent scanners that use 3 color tubes -
won't work either. Mine is an old AGFA 1212. Of course, resolution is
only 1200dpi.

John