Digital BW, The Print

Daniel: I do not now have the link to look at your image. Newton rings can not occur when the film is perfectly parallel to the glass.  That is most likely to be the case for the edge of the film that is close to the carrier at its supported edge. The unsupported edges however will not be parallel to the glass bed.  Newton rings are caused by interference of the reflections from the glass bed and reflections from the film base. For that to happen there has to be some curvature to the film.  The diameter of the Newton rings will vary according to diameter of the film's curvature, accordingly I have to wonder if in some cases, that diameter can be large enough for the rings to look like straight lines.
I do not know what role static electricity has in all this, but In winter in heated areas there is a great deal of electrostatic electricity and film is like a condenser and can carry quite a charge.  The very dry conditions during the scan worsen as the film sits under the scanner lamp for some time.  I too have seen this problem but it tends to occur when the scanner light has been on for some time with the film under in the carrier.  I still do not think that this is a problem with the scanner and an easy experiment will quickly put that to rest: Before the scan, place the film in a plastic box where you have put a damp cloth in, to allow it to absorb moisture and cause the film to curl in a convex shape relative to the emulsion side. After you allow the film to soak up some of the humidity do the scan but do not let the film dry up again by keeping it under the lighted scanner for longer than needed. If the problem is not in the scanner, the scanner the bands should disappear.   

You are in Norway, surely you have the heating on at this time of year? At what humidity do you keep the house?   I work in the basement where the humidity tends to be higher, now at 45%.  As the season progresses in Canada the air in the house becomes much drier, until I start the humidifier.  I think these problems are usually caused by film curl.  As the film dries up, the emulsion side -which is hydrophilic, shrinks while the backing, which is hydrophobic, does not. The imbalance causes the curl.  Even when the film and backing are at equilibrium the film will not be perfectly flat when it sits on a scanner due to gravity.  The only way to get rid of the problem is to use glassless scanning as in some the Microtek scanners which use two light sources, above the glass bed for reflective, and below the glass bed and under the film for transparent materials.  The bands which Nikon scanners are well known for are another different matter and not related to Newton.  I do not think that the E3200 suffers from these problems.
Good luck,

Julio Fernandez
  ----- Original Message ----- 
  From: Daniel Staver 
  To: DigitalBlackandWhiteThePrint@yahoogroups.com 
  Sent: Sunday, November 30, 2003 12:09 PM
  Subject: RE: Re[2]: [Digital BW]  Banding on a scanner


  > Those are Newton rings.

  I don't believe they are. If you look at my example you'll see that I
  have perfectly vertical streaks throughout the entire image, even very
  close to the edges. Newton rings have a much more random appearance,
  looking more like rings than lines.

  --
  Daniel Staver
  http://daniel.staver.no 




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