[filmscanners] Re: Avoiding Newton rings

["Arthur Entlich" <artistic-1@shaw.ca>]

Anthony Atkielski wrote:

> Paul writes:
>
>
>>Even anti-Newton glass degrades the image. It's
>>quite obvious with an anti-Newton glass slide mount.
>>
>
> It should not make a difference if it is only on the side of the film
> opposite the scan head.  If it comes between the film and scan head, that
> might be a problem (doesn't seem to be the case on the LS-8000ED).
>


I'm not sure I accept this statement.  If the texture is visible in
scans, it would show up on either side, unless the depth of focus/field
had a very fast drop off to limit the ability to have the texture in
focus. With the surface of the anti-newton glass being literally
contacting the film surface, I would expect any texture would be
recordable regardless of which side it appeared on, relative to the
scanning mechanism, being that the scan is a transmissive type, not
reflective.

I find most E-6 slide films today have a very glossy emulsion side,
making newton rings more likely on both sides.

As you may recall, Roger Smith found that the most surface transparent
layer on the emulsion side seems to be the one containing the "bubbles"
which were being recorded by some scanners are "pepper grain".

This surface may be there to help protect the emulsion surface from not
only mechanical damage, but from fungal growth.  Years ago a lacquer was
used to coat the emulsion surface, but this was eliminated.  I wonder if
this final clear coating absorbs or contains anti-fungal chemicals?

Art


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