Scanners: Scanning Autochromes and Dufaycolor glass plates

[richardsullivan]

I have read and researched quite a bit on how to get the best scan or repro from my color glass positive transparencies: Autochromes, Dufaycolor and Agfa Farbenplatten.

High-end scanning quotes here in Hawaii start at more than $100 per piece, more than I paid for many of the plates themselves. So I made a mask holder from black foamcore, taped it to a lightbox and shot them that way with my Canon xti SLR. Problem is, the grain that is inherent in Autochromes is never sharply focused with this method, despite many do-overs, and that grain is a crucial element of the picture. The autofocus doesn't zero in on it, even when I turn the plate emulsion side up or down. When I try focusing manually I cannot see the grain clear enough to see whether it is shaply focused or not.

I have seen recommendations here about scanners that will backlight transparencies and scan them, but had anyone specifically tried scanning glass Autochromes or Dufaycolor plates? I cannot invest in yet another scanner without knowing if I can get the result I want. The ArtixScan M1 Pro seems to be a good choice but there are many complaints about the very problematic software.

If any of you have done high-quality scans of autochromes or other color glass transparencies, I'd greatly appreciate hearing your experience...or if I've missed a thread here that has dealt with this, please post a link. Thanks!

[Mike]

A few thoughts:

Taping to your light box maybe a problem, is the light diffusing filter in the light box is close enough to the film to be in focus?

To get the grain in focus, place the original so that the emulsion side is toward the camera. Place something like a small piece of paper across part of it (flat against it) so you can focus on the edge of the paper (in the manual mode). Select a F stop like 11 or 16, this should provide enough DOF so the grain will also be in focus.

Use something like a cable release or the camera's self time to help eliminate any camera motion even though the camera is tripod mounted.

[Kraellin]

i've never worked with glass transparencies, but i have worked a bit with plastic ones. the light box is a good idea, but try putting a piece of white paper between the light box and the transparency and see if that doesnt help.

also, definitely use the manual focus. set it on a tripod and find something else to focus on over the lightbox to set the range of the focus, something you can focus on. then, simply replace that with the transparency and it shld be in focus.

[Mike]

Another thought:

Make sure that no light is hitting the side of the slide that you are looking at. Its best to shoot this in a darkened room so there is no possibility of any glare or reflections on the slide.