Re: [APML]: scanners

[Anders Thulin <Anders.X.Thulin@telia.se>]

Bobby Middleton wrote:

> and they were much better than any print shots I had done so far.....  So
> is anyone out there proud enough of their flat bed scanner
> to recommend it?  Are these type scanners good enough to do
> astrophotography work?

  Scanners differ a lot, and one scanner that does superlative work in
one area of application can be rather bad in another. It also depends on
what type if scans you'll do. Hi-res, print quality scans needs some
care, and probably some way to calibrate the colour display. If youre going
to print the images on a colour printer (ink-jet, sublimation, etc.),
it's also a good idea to ensure that the scanner/printer combination
works together.  

  Keep an eye on the true resolution of the scanner, if resolution is
important to you. The nominal resolution is almost always the nominal
resolution of the CCD element times the stepping rate. Actual resolution
must be measured, not extrapolated. But then, high resolution
is usually less important to most users than they think.

  If you read up on scanner tests (like those in PCWorld), check if they
have used 'default' settings for the tests or not.  Tests are easier to
do if you don't fiddle with controls, but then you can't be sure the
default setting is optimum for what you want. Caveat lector.

  The best idea is almost always to ask a dealer for a chance to try it
out for more than five minutes, particularly to scan *your* images, rather
than the standard test images they may have around. 

  I've been using a HP 3c for several years, mainly for OCR work
(which only requires good contrast and  good resolution for black-and-white
images). Those times I've scanned colour photos I've always been able to
get the colour balance I wanted -- or rather, in those cases I didn't get
it right, it was usually a question of waiting for the scanner to get warm.
Then, I've been working in fairly low resolution (<200 dpi for colour).
I have lately scanned a couple of astrophoto prints without any complaints,
but my eye for defects is probably not developed much beyond B/W yet. 

  There is a slide scanner attachment available, but I have no idea
if it works well or not. By the way, now I think HP has upped the 
scanner version number to 4 or 5, at least. 




Anders Thulin       Anders.X.Thulin@telia.se        013-23 55 32
Telia Engineering AB, Teknikringen 6, S-583 30 Linkoping, Sweden