Oregon Star Party 2010
Telescope Walkabout
This year's walkabout was one of the best in recent memory. Let's get right to the telescopes and their builders.
Leif
Edmondson's 16 inch f/5.5 features nice woodwork. It can be
setup in 10 minutes. Leif rebuilt the secondary cage to improve
interaction with the trusses. Leif had fun building the scope; it
has good optics. He hopes to build a lighter scope the second
time around.
Arthur Guilfoil's 4 inch f/15 brass refractor
features a brass mounting with titanium shaft in ball bearings and a
fully baffled aluminum tube. He did all the machining including the
focuser drawtube and remounting the eyepiece lenses. If that
wasn't enough to impress, Arthur also machined all the gears and built
the gravity drive from scratch. The telescope took 13 years to complete.
Tom Clarke showed how he stows his telescopes in his RV as he travels from star party to star party, doing 'RV Astronomy'.
Mel
Bartels showed his 13 inch f/3.0 in a new folding mounting. The
mirror is a meniscus shaped, constant thickness, plate glass mirror,
using a fan for rapid cooling and steady images. Because of the
meniscus' strength, only a simple 3 point back support and 2 point edge
support are needed. The mount's center of gravity is located at
the mount's mid-point, minimizing eyepiece travel, balance issues with
heavy eyepieces and the mount's overall footprint. The observer
sits in a low chair for observing from horizon to zenith. The
altitude bearings also function as truss tubes, replacing all but two.
The telescope folds to a foot and a half cubic box in about a
minute and weighs 25 pounds. Finally, the upper ring uses a new
reduced diameter design, based on the reduced diagonal size possible at
f/3.
Nate Gilman's 8 inch string Dob was built for school
credits. He finished the spider the morning of the star party,
christening the scope 'Wendy'. He used simple inexpensive
material such as copper tubing for the trusses and a pot lid for the
mirror box cover.
David Birch's built a custom horseshoe mount
for his 16 inch Meade Lightbridge. He uses an offset yoke design.
David built the mount so that he can take long exposure digital
images. The mount is all built from scrap recycled material.
A table top comprises the mount while JMI motors provide the
motorized movement.
Don Peckham's 8 inch double stacked string
scope takes string technology to a new level. Don has arranged
the strings, tension tubes and flex rings such that there is no
bending. The strings form large angles. There are no
turn-buckles.
Ken Lulay's folding 8 inch f/3.8 caught all by
surprise when he showed it collapsing into a small box in a matter of
seconds. The telescope in it's entirely weighs 10 pounds.
Note the ring secondary. The scope is a father and son
effort, finished just in time for OSP.
Roger Garcia and
Lynelle Wilcox's 10 inch f/5 Dob is based on the San Francisco Sidewalk
Astronomers Design. He says that the design is easy to build.
It includes a tailgate mirror cell. Cost to build the
scope was $80. Of particular note are his folding adjustable
height chairs.
Skip Laub's 12 inch f/ 6cedar wood tube is a 40
year project. The tube is built from cedar strips coated with
fiberglass. He also built the mounting. Skip also showed a
companion 8 inch scope.
eod