OF THE ROGER N. CLARK

PREFACE
During research for this book I found the
answer. The impression that higher f/ratios
by themselves give a better view is largely
wrong. The true reason is partially what this
book is about. The magnification used, not
the f/ratio, determines what can be seen in a
very faint object. A higher f/ratio telescope
simply yields higher power with a given
eyepiece, and therefore it is more likely to be
used that way.
In August, 1982, I gave a talk to the
Hawaiian Astronomical Society, an amateur
club, in which I discussed how the human
eye detects light at low levels and how va-
rious objects appear through telescopes.
Many beginners see the beautiful pictures in
astronomy books and expect the same views
in their telescopes. This often results in disappointment.
But I have found that if
amateurs know more of the characteristics of
the eye, and use the telescope a little differently,
quite a lot of detail in galaxies, nebulae,
and star clusters can be seen.
The response to that talk convinced me
that this material should be presented to all
amateurs. It was then that I decided to write
this book.
Roger N. Clark
Denver, Colorado
Acknowledgements
As with any large work, there are many who
helped in the creation of this book. I would
like to thank Herman Dittmer, Ray Fabre,
Ivan Giesler, Bob Gunnerson, Ruthi Moore,
Mike Morrow, Milt Sher, and Bill Tittemore
for their reviews of various drafts of the book.
Their comments helped my ideas evolve to
the present work.
I wish to extend a special thanks to Alan
MacRobert of Sky Publishing Corp. fo r his extensive
review and editing. Alan is the only
editor I have known who can take a rough
manuscript and change it into a flowing work
without changing any of the original ideas.
His knowledge of astronomy and attention to
detail assured that every thought was correct
and understandable.
Finally I wish to thank my wife, Susan, for
reviewing parts of the book and sons Matthew,
Christopher, and Tyler fo r putting up
with my many hours spent at the computer,
and the many nights observing far from
home.
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