Re: filmscanners: Emulsion flaws (was dust in SS4000)

["Owen P. Evans" <opevans@istar.ca>]

Hi Martin,
I can tell you that dust is everywhere! If you handle slides with cotton
gloves, the slides become filthy. If you place the slide into the slide
holder it will grab any dust that you let get on the holder while it sat on
the table. The minute the motors start whirring in the scanner, the
electrostatic charges pull dust in from all around the scanner. I scanned a
slide which I made a year ago and compared it to the scan of it I made 10
months ago. The slide sat in its Print File sleeve for 10 months. I cleaned
the slide with a sable artists brush, then compressed air ( Dust Off ) and
scanned it. The scan looked like I dumped an ashtray on the slide???
Compared to the first scan I made, it was worse.
My theory is that the slides themselves not only attract dust
electrostatically, but degrade and crack over time. These micro-cracks
aren't seen when we project the slides but under the microscopic scrutiny of
the scanner, become larger than life. Once the cracks open to the
atmosphere, all sorts of things can get into the emulsion layers of the
slide. Art & Roger are taking the manufacturers to task in their theories;
I'm just accepting the chemistry & physics.
Again, when we blow these slides up in Photoshop, they are magnified beyond
the 8 x 10" or 13 x 19" prints that we make so the spots become exaggerated
on the screen not in the prints. I've printed a lot of scans from the
SS-4000 to an Epson 2000P printer in the past 10 months and I don't see the
crud in the print; only on the CRT of the computer.
Just my two cents worth of opinion.
Regards,
Owen

Owen P. Evans
Osgoode, Ontario. Canada
(near our nation's capital; Ottawa)
opevans@istar.ca
J.33-3
----- Original Message -----
From: "Barbara & Martin Greene" <martbarb@earthlink.net>
To: <filmscanners@halftone.co.uk>
Sent: Saturday, September 22, 2001 8:46 AM
Subject: Re: filmscanners: Emulsion flaws (was dust in SS4000)


> Art, Roger and others
>
> What you have found offers a plausible explanation for the junk that has
> been plaguing many of us although not seen or of concern to others.  I
just
> finished removing at least one thousand spots from a scan.  This was from
a
> pristine, perfect slide scanned on an SS 4000, blown up for a 13x19 print,
> and rubber stamped in Photoshop.  Clearly, they were not the result of
dust.
> Nor was it from my brand new scanner.  The slide was processed by an
> excellent lab.  The only explanation for this is that they are in the
> emulsion.
>
> Martin
>