If you are
aiming for high quality prints or in this case T-shirt designs,
then aim to scan in all your media at 300 dots per inch. This
will ensure that your images do not look bitmapped, ie with jaggy
edges when printed. The image below is taken from the TWAIN scanner
driver which works with a variety of scanners and software. The
scan is set at 'color RGB' meaning that it will create an image
made up from levels of red, green and blue. The scale is 100 per
cent, so the image will be 'same size' when scanned. It is a good
idea to do a preview before you do the final scan just to check
what it will look like.
Screen based
computer projects (web sites or CD roms) require just 72 dots
per inch. You will note that your scanner software allows you
to set the number of dots per inch. This is where the memory management
comes in, because if you are scanning at 300dpi you will soon
end up with large files. An A4 document scanned at 300dpi will
result in a 24mb file size.
For early
tests and try outs in class, scan in at 72dpi which cuts down
the processing time and increases the work flow. But remember
to scan in at 300dpi for final artwork. Note - it is not possible
to convert a 72dpi image to 300dpi because the dots are not there.
You can scan
three dimensional objects on a flat-bed scanner with surprising
results. Most scanners enable you to lift the top lid off and
you can place the object on the glass bed. In place of the lid
use a white sheet or cloth of some kind over the top of the object
to mask out surrounding light. Be careful not to scratch the glass
with sharp objects.
