In any such instrument, the focuser
is paramount, and the dual-speed focuser
Several other scopes in the field sported versions of his signature finderscope mount and focuser
designs, a testament to his dedication in making it possible to produce viable instruments from basic materials.
is multi-purpose as various tubes carrying different pieces of apparatus had to be interchanged during observing sessions; there are no focusers
in the commercial field which are capable of this facility, but my focusers
This solidly built 80-mm (3.1-inch), 526-mm-focal-length (f/6.5) Newtonian has a novel feature: the helical 1.25-inch focuser
has a built-in finder that shares the eyepiece view with the main scope.
Now included are a 2-inch focuser
with a 1.25-inch adapter for the supplied 10-mm (120x) and 25-mm (48x) eyepieces, a navigation knob grip, and 6 x 30 finder.
Although the 115 did a nice job on medium-sized deep-sky targets, it was with the big objects that it really shone, With a 35-mm wide-field eyepiece in the focuser
, I had stunning views of the huge North America Nebula (NGC 7000) and both bright sections of the Veil Nebula.
I attached lightweight steel-cable "safety lines" to a couple of these to ensure the camera wouldn't fall to the ground should it accidentally slip from the focuser
Werner says, "I kept being a pain in the you-know-what to Roger, and he kept coming up with better and better designs." What they wound up with is a set of corrector lenses that fits partly in the focuser
drawtube and partly in front of the secondary mirror.
(With such a minor obstruction, this scope is a planet killer!) It's mounted on a single rod that's held in place by a thumbscrew on the focuser
The FCD100 series comes with Explore Scientific's standard HEX focuser
, a Crayford-style unit with both coarse and 10:1 fine focus adjustments.
Howard remembers: "I came up with a much more complicated version made from a mix of materials that could rotate around the focuser
, which worked but was rather flimsy and didn't rotate easily.
With its dew shield retracted and no adapters attached to the focuser
, the FSQ-130ED is impressively compact, being slightly less than 21 inches (53 cm) long.