RE: [Leica] scanning Leica slides vs colorneg

["Tim Atherton" <timphoto@nt.sympatico.ca>]

For in depth film scanner comparisons, including LS2000 and Pol 4000, see:

http://www.cix.co.uk/~tsphoto/

Look under film scanners. Also home to the film scanner list.

Tim A

> -----Original Message-----
> From: owner-leica-users@mejac.palo-alto.ca.us
> [mailto:owner-leica-users@mejac.palo-alto.ca.us]On Behalf Of Henning J.
> Wulff
> Sent: September 27, 1999 10:50 PM
> To: leica-users@mejac.palo-alto.ca.us
> Subject: Re: [Leica] scanning Leica slides vs colorneg
>
>
> At 5:34 PM -0700 9/27/99, Godfrey DiGiorgi wrote:
> >> It is my understanding that your typical scanner is really not up to
> >> snuff to slides and does better with ColorNeg while a Polaroid 4000
> >> can deal with slides fine. By the end of the year who knows the
> >> options but can anyone confirm this or know much about it?
> >
> >Transparencies, being positive images, have more dynamic range than
> >negatives (the materials are not sensitive purely linearly, the response
> >curves are better characterized as partial differential
> equations of order
> >2 - the useful range of exposure tends to happen in the toe and linear
> >section of the curve, each transfer from negative to positive includes a
> >rise in contrast just like making slide duplicates includes a rise in
> >contrast). What limits scanning of transparencies is similar to what
> >limits making good prints from transparencies: the contrast gain of a
> >slide which has just too much dynamic range burns highs and loses lows.
> >
> >Given this, the limiting factor in how well you can scan a
> transparency or
> >negative has to do with the scanner's bits per channel which relates to
> >its DMax capabilities (as well as all the other details of quality
> >alignment, good focus, etc). Shooting transparencies for scanning is much
> >like shooting them for printing: you have to be careful to keep the
> >significant portions of the slide to a tight lighting ratio not only to
> >keep within the transparency material's exposure tolerance but also to
> >minimize contrast gain. A 12 bit per channel scanner at 2700 dpi will do
> >quite a good job with slides where a 10 bit handles only the better
> >exposed slides well, and an 8 bit unit's capabilities are rather limited.
> >Most negatives scan very well even with 8 bit units, although 10-12 bit
> >units do seem to wring more brilliance out if properly calibrated and
> >adjusted for the film. Part of this might be that the more expensive
> >scanners generally get better software as well, part of a professional
> >package.
> >
> >Added dpi resolution surely helps no matter what but the limitations here
> >are more related to how much detail your digital image will have at what
> >enlargement size rather than how well it will reproduce the color/tonal
> >scale. A 2700 dpi film scanner, calibrated properly, will return enough
> >pixels to make a quality 12x-16x enlargement from 35mm format (16x is
> >about 170 ppi, 12x is a healthy 225 ppi). While this doesn't beat the top
> >notch printing technology available today, it's adequate for
> most people's
> >home uses. Going to 4000 dpi gives you closer to the drum scanner
> >resolution capabilities if you want really large prints.
> >
> >Something must also be said for the fact that some scanners and their
> >drivers are better optimized for transparencies vs negatives and vice
> >versa. Part of the reason I chose the Polaroid Sprintscan 35E/S (10bit,
> >2700 dpi, built-in DSP) was that in testing it, it seemed to be much
> >better at rendering color negatives than the comparably price Nikon
> >scanner was in 1996, the Nikon at the same price was better at rendering
> >slides.
>
>
> The present Nikon LS-2000, intrinsically, and enhanced because of its
> multisampling capability does a better job of producing a decent
> slide scan
> due to its lower shadow noise than the Polaroid 4000, as I mentioned in a
> comparative report a while back. The extra detail available with the
> Polaroid is not enough to compensate for its bad software and more limited
> dynamic range. The LS-2000 is still a better value if your interest is in
> slide scanning.
>
> Adveritised Dmax and dynamic range capabilty are generally
> nowhere near the
> truth, and dpi capability is also generally less. Caveat emptor!
>
> For more information see the scanning mailing list; to subscribe:
>
> send to : Majordomo@leben.com
>
> the following message:
>
> subscribe scan 'your e-mail address'
>
>    *            Henning J. Wulff
>   /|\      Wulff Photography & Design
>  /###\   mailto:henningw@archiphoto.com
>  |[ ]|     http://www.archiphoto.com
>