Brand new. Fully described on William-Bell's web site. List $30 plus S/H, I'll sell it for $20 plus $4 S/H
Here is capsule summary from web site:
"While the star test has been around for centuries learning it has often
been hampered by messy mathematics and its visual nature. Most
people who use it have learned it at the elbow of a patient Master. In
this book, Dick Suiter becomes your Master. He carefully shields you
from difficult diffraction theory and uses advanced computer generated
graphics to show you the appearance of each aberration. Again and
again, you will look at Dick's graphics and say “I've seen that before.
So that's what it was!” The star test is a powerful but inexpensive way
of obtaining better resolution and contrast. With this book most
observers will find that they don't need a new telescope because they
now can test, diagnose and fix the one they have. Using Star Testing
Astronomical Telescopes as a guide, your telescope will perform to the
best of it's abilities and perhaps it will show images better than you
would have believed possible."