View Full Version : Scanning with AN glass

Ed Richards
16-Apr-2012, 13:23
I have been looking at some of the rigs in which you tape your negative to AN glass, which is then suspended over the scanner bed so you scan through the AN glass and the negative hanging below it.

How hard is it to get the tape residue off the negative?

Can you scan through AN glass, i.e., could you sandwich a negative between two pieces of glass with the AN surfaces on the inside of the sandwich, and the sandwich then shimmed above the scanner bed so it is not touch the scanner bed? This would be an easy way to have a flat negative and no tape.

How much does AN glass affect the image if you scan through it?

Henry Ambrose
16-Apr-2012, 13:30
Hanging below won't help with film flatness.
Tape residue is no problem at all, nothing to remove, really - depending on tape used.
Yes you could scan a sandwich but I'm not sure it will be helpful.
I'd work on a way to hold the film under tension with no glass contact at all, or fluid mount instead.
TMax100 is about the only film that has a problem with newton rings when laying directly on the glass emulsion down.

16-Apr-2012, 13:41
Use Scotch Magic Tape, the real one; you'll have no residue, and it really holds the film well.
Scanning through two pieces of glass will likely deteriorate the scanned image.

Ed Richards
16-Apr-2012, 14:07
Sadly, Tmax 400 is even worse than 100.

16-Apr-2012, 15:54
I've got AN glass from Focal Pointe and have been having trouble with it and Portra. Always Newton Rings. On my 4990 I have the platen-negative face down towards platen-AN glass foggy side against film. Negative/glass propped on pennies off the platen. I thought that's how the directions stated to use it but I still get newton rings. Sandwhiching between glass has made them worse.

16-Apr-2012, 16:01
Try ground glass instead of AN, obviously only above the neg. But taped to that, air space below, should be ring-free. The GG might lower contrast slightly, though I've found it easier to manage tonality using this method.

Peter De Smidt
16-Apr-2012, 17:27
With consumer flatbeds, the sensor and lens are under the glass platen, and the light source is in the lid. If you tape a negative to the bottom of a sheet of AN glass and use feet to hold the glass off of the scanner platen, then you are not scanning through the AN glass. The light is going from the light source and through the AN glass, negative, scanner glass, off a couple of first surface mirrors, through a lens, and onto a sensor. You don't want to put AN glass between the negative and the sensor unless you really have to. It will limit what you can resolve. You'll get smears instead of sharp grain, for example. This might not be noticeable, though, depending on the resolution of the scan.

Ben Syverson
16-Apr-2012, 17:49
I've seen granularity from scanning through AN glass at 1200 DPI on an Epson... So you definitely don't want to scan through it. The "suspended upside-down" method is best.