SkyandTelescope.com September 2014 732012, p. 62). Crucial to the process was
star testing throughout the fi guring stage.
Although terribly time consuming, this
enabled him to monitor progress with
a great deal of accuracy and sensitivity,
while also evaluating the entire optical
train as a complete system.
But the eff ort paid off. “I cannot get
over how beautiful the ultra-wide-angle
views are — it’s like pulling back the cur-
tains and going from a peephole to seeing
a grand vista,” says Mel. “Every object I’ve
seen before is worth viewing again and
seeing in a new light.”
If this whets your appetite for a super-
fast telescope of your own, there’s only
one way to get one: build it yourself. Is
that feasible? Probably not as a fi rst-time
project, but if you’ve already made a couple
mirrors with normal f/ratios, a fast optic
such as this is within reach. Skill and
patience are prerequisites, and as Mel
notes, “I don’t see how one can escape
using the star test, since the fi gure is so
touchy — and it takes hours on a night of
good seeing for a single critical test.”
Readers wishing to learn more about
Mel’s 6-inch refractor can visit: http://
tinyurl.com/mkwjcyz. ✦Contributing editor Gary Seronik is an experi-
enced telescope maker whose fastest mirror to
date is a pedestrian f/4. He can be contacted
via his website, http://www.garyseronik.com.At fi rst glance the scope looks like a conven-
tional but stubby Dobsonian. Note that the
side bearings are off set to ensure the scope will
remain balanced with a heavy eyepiece, even
when aimed vertically.MEL BARTELSSell Your Used Equipment
— For Free!
SkyandTelescope.com/Sk marketplace
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