[Leica] Re: Digital storage???

[Donal Philby <donalphilby@earthlink.net>]

Jim Brick wrote:
> 
> If your output is going to be film (quality hopefully equaling the
> original) for optical enlarging on perhaps Ilfochrome, you want to capture
> (scan) as many pixels as possible. But you should only scan at the dpi of
> the film imagesetter.
> 
> To make things simple, let's assume that 35mm is 1"x1". A good drum scanner
> can record at 8000 dpi. 8000x8000=64 megabytes. But there are three colors.
> R, G, & B. So each pixel is recorded three times to produce a 3x64MB file
> (192 megabytes.) Or times 4 for CMYK (256 megabytes). This is not all of
> the information available on 35mm. It's all that an 8000 dpi scanner can
> produce. Now take this out to 4x5 (my interest) 32,000 x 40,000 x 3 = 3.84
> gigabytes and you still don't have *all* of the available information. You
> only have what the scanner is capable of delivering. But for the printing
> industry, you don't usually need an 8000 dpi scan. An 8000 dpi scan of a
> 35mm slide can produce a file capable of being printed at about 30"x36" on
> a 400 dpi printer.

Jim,
which leads to the conclusion that for printing on a printing press of
almost any magazine size images, there is absolutely nothing to be
gained from using anything larger than a Leica.  I find this is true and
not true.  Why do color separators always want larger images and why do
they sometimes print better?  Perhaps it is the quality of the lens in
the scanner??  All I know is that it is very difficult for me to tell
the difference in print between what I have shot 35 and 67 or 4x5 if the
scanning house is of quality.  But why should it be more difficult to
scan 35 than 4x5?  

The most wonderful thing about Evercolor prints is that they are so
detailed that the difference bwtween a 35 and 4x5 original when printed
large by the process is very hard to tell apart.  I remember seeing
Galen Rowell (35 Nikkor) and David Muench (probably 4x5 Schneider)
Evercolors side by side and just being so happy to find proof that I
don't need to shoot 4x5.  the real comparison was between the Rowell
evercolor and the same image by R or C print in the Nikon booth at a
trade show.  Night and day.  

Thanks for the erudite post.

Donal Philby
San Diego