Digital BW, The Print

> Another question.  To know that I have the image scanned
> correctly...wouldn't the Photoshop/Image Size-resolution be between
> our 240 & 480 for quality.  Or to ask another way, where do I confirm
> in Photoshop the resolution of the scan?

Clevis,

The apparent good wisdom of your book aside, what most people do is to scan
at the highest resolution their scanner is capable of, before it resorts to
interpolation. This is referred to your scanners "native" resolution. In
most cases this resolution will give you the sharpest scan the scanner is
capable (drum scanners are different as they use apertures which can allow
for various "native" resolutions.

Now to your question: in Photoshop go to the IMAGE menu and scroll down to
Image Size. Uncheck the Resample Image check box. With this box off, changes
you make in this dialog box will not change your image pixels, so you can
alter your size settings, or resolution settings, without fear of altering
your data. Now as you change either of your images dimensions the other
dimension will change accordingly. Remember, since you aren't altering image
data, a change to any of these settings will have a proportional effect on
the others, as all you are changing is the scale of the image. Thus, alter
the image size and read the images resolution at that size. Or, set the
resolution to 240 PPI to read what size your image will be at that
resolution.

Most people just allow the resolution fall where it may, provided it is at
least 240 PPI. Remember, at this point we are discussing data which as yet
has not been resampled up or down by the scanner. If your resolution at your
print size would be lower than 240 PPI, you will get differences of opinion,
and probably need to test for yourself regarding whether or not to resample
the image up to 240 PPI, or print at whatever resolution your file is. I
haven't done much printing below 240 PPI, though the few times I tried, I
did get acceptable results down to 150 PPI. What is considered acceptable
will vary by how critical people want to be, the nature of the image itself,
the quality of the scan, the printer model in use, and whatever else I'm
forgetting. On the other hand many people find that Photoshops resampling is
acceptable up to a 100% size increase.

This Image Size dialog box is where you would do that resampling. You'd
check the "Resample Image" checkbox and enter your desired resolution. Most
people find that resampling softens the image, so a touch of UnSharp Masking
(USM) will be required to compensate.

Confused yet? Hope something in there was useful.

Todd