Re: [APML] More SS4000 scanning questions

["Don Westergren" <westergren@netzero.net>]

Hi Alan,

Jerry's book has a short discussion of "spatial resolution" in chapter 1
where he says that 2700 dpi is adequate, but that some films can go to
higher resolution, all the way to 8000 dpi.  There's no set "Best"
resolution for scanning.

I believe the choice depends on the equipment you have and what you want to
have as the result.  For instance if you have a scanner with optical
scanning at 2700 dpi, that's what you should use.  Going to 4000 dpi with a
2700 scanner would require interpolation, either by the scanner or in your
computer/Photoshop.  If you want to produce a print at 8x10 inches and you
use a printer with 360 dpi (or multiple) then you may want to start with a
scan about 3200 dpi to avoid any interpolation of pixel information.  If
your printer uses 300 dpi or multiple, then 2700 is fine for an 8x10.  Want
to go for 11x14? Then a 360 printer needs 4000 dpi scans.  I really try to
avoid any resizing of a picture that would require dividing or multiplying
pixels by anything other than an integer in the scanner, computer, and
printer.

Don

> 4. I've asked this before and the answer made sense. For 35mm color
> negative film, is a scan setting higher than 2700 dpi useful? I had
> someone tell me in an off-topic discussion on the Losmandy group that I
> should be scanning at the highest resolution, 4000dpi in this case.
>
> 5. In a related question, should slide film (E200) be scanned higher
> than 2700dpi, seeing as it has higher contrast?



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