Dr. Frank Melsheimer
DFM Engineering, Inc.
1035 Delaware Avenue, Unit D
Longmont, Colorado 80501
It has been a little over a year since
DFM retrofitted our 1.6m telescope here at mont Mégantic and I want to let you know
how much we are pleased with the result.
Our 25 year-old Perkin Elmer telescope had
been performing rather well under extreme climatic conditions (from -30°C in January to
+30°C in July) but some of its mechanical parts were starting to show signs of wear in
recent years. The manual
TCS-Sky console was also becoming less reliable and replacement parts for its electronics were
almost impossible to find. This resulted in observing time losses at the telescope for our
students and staff. Based on my observing experiences at CTIO and MDM, where I became familiar
with your companys work, I strongly suggested to the observatorys scientific board
that DFM be contracted for a major upgrade of our telescope. Let me tell you that we are very
glad we did!
Right from the start, every aspect of the retrofit
was handled smoothly and professionally - from Mark Kelleys initial visit to the observatory
in January 2000, to the actual retrofit in May 2001, and the one-year follow-up service to
iron out the very few minor problems we encountered. I was particularly impressed with Mark
Kelleys and Ian Huss skillful
operation on our patient. Within a week, major mechanical and electronic
components were replaced with modern sturdy parts. New motors and encoders were installed on
all three axes (RA, Dec, and focus), the instrument rotator was also motorized and encoded,
and a new computer controlled TCS-Sky system was installed. All in all, the telescope was down
for 5 days (nights) only, of which the last two were used to refine the pointing model.
For the last 14 months we have been able to
appreciate the benefits of DFMs fine work. The telescope absolute pointing has improved
with an overall accuracy better than 10 arc seconds. The telescope tracking is smoother than
before, in fact, our autoguider does not have to work as much as before; typical PSF of stars
on unguided 20 minutes exposures are about 2-3 arcsec. Finally, the TCS system is fast and
easy to use. The net result of this upgrade is a 10-15% gain in efficiency of the telescope
observing time. Given that we get about 120 clear nights a year at our observatory (typical
climate for northeast america), its like getting an extra 15 clear nights every year
- time enough to complete one or two more scientific projects. Thats a real bonus!
From the astronomers, the students, the night
assistants, and myself, congratulations for a job well done! It has been a pleasure doing business
with you (and we hope to do some more in the future).
Observatoire du mont Mégantic
Université de Montréal