Re: filmscanners: BWP seeks scanner

[Arthur Entlich <artistic@ampsc.com>]

I won't argue that CCD scanners do not typically capture the resolution
I am referring to.  In discussions with Phil Lippencott several years
ago, he indicated to me that a properly captured 35mm Kodachrome slide
(I'm not recalling if it was a 25 or 64 ISO film) could produce a
close to 150 meg file without adding noise to make the file that large.
    I assume this was at 48 bit depth.  He was using a drum scanner, and
he told me that was about the number the thing plateaued out at.

I am relatively convinced good films with good lenses can record over
4000 dpi (as captured by a CCD scanner).  Part of this might well be
that a 4000 dpi CCD scanner doesn't come close to capturing 4000 dpi,
which I suspect is the case.  Since I know that the rated 2400 dpi HP
S-20 was "clocked in" at under 1000 dpi, I somehow doubt that the 4000
dpi models came close to that number either.

Art


Raphael Bustin wrote:

  >
  > On Fri, 15 Jun 2001, Arthur Entlich wrote:
  >
  >
  >> You don't directly mention the size of the prints you wish to produce,
  >> although you allude with the 870 printer something like 8 x 12" or
  >> smaller.  Unlike silver images, which simply have larger grain 
making up
  >> the components of the image, without any true resolution loss, in the
  >> digital realm, since even 4000 dpi scanners do not capture all that is
  >> on a 35mm frame, you end up with softness and loss of detail if you go
  >> too large.
  >
  >
  >
  > While I know that this topic has been debated
  > many times, on many forums, I've come to the
  > conclusion that perhaps that very high estimate
  > of film resolution may be optimistic.
  >
  > I've never seen a drum scan of any of my slides
  > or negatives, but I've seen scans from a large
  > variety of CCD scanners, including the SprintScan
  > 4000 and now my 8000 ED -- both rated at 4000 dpi.
  >
  > In a nutshell -- I don't really see a significant
  > increase in sharpness going from 2700 dpi to 4000
  > dpi.  And this is with slow (ISO 100) negative
  > films like Reala, Supra, etc, using decent optics
  > and with the camera on a tripod.
  >
  > What I do see from these hi-res scanners is lower
  > noise, and better tonality.  With the 8000, I'm
  > enjoying the extra dynamic range. But I'm not really
  > seeing a major increase in sharpness or apparent
  > resolution.
  >
  > Maybe one needs to go with fancy German lenses to
  > see that.  Or maybe it's the case that the scanner's
  > internal optical system is the limiting factor.
  >
  > Whatever the reason -- my point is that this claim
  > of "greater than 4000 dpi" for the effective
  > resolution of film is rather optimistic.  I'm curious
  > what it would take to actually observe and realize
  > such a high resolution.
  >
  >
  >
  > rafe b.