iOPTRON - Astronomy Technology Today

THE RIGEL SYSTEMS USB NSTEP AND ASTROSYSTEMS COLLIMATION TOOLS
The AstroSystems LightPipeSight-
Tube Combination tool features a unique
“non-directional” illumination cap. If
you’ve used a classic Cheshire, you know
how frustrating it can be to try and keep
your flashlight in perfect alignment with
the narrow illumination port with one
hand while trying to make fine adjustments
to collimation screws with the
other. The AstroSystems illumination cap
captures light from any angle, making it
far easier and more enjoyable to use.
After using the LightPipe/Sight-Tube,
my collimation was better, but still not
perfect! I moved on to the Autocollimator,
which AstroSystems describes as “taking
some practice” to use perfectly. Practice
indeed! What first appeared difficult soon
became second nature. At first glance, you
install the tool and see multiple reflections
of the center spot. It was so sensitive to
alignment, that simply touching one of the
focuser set screws caused several of the
reflections to jump. No doubt this thing
would show me any remaining issues! In
simplest terms, the goal of the autocollimator
is to get the reflections to converge.
If you are close with the LightPipe, it won’t
take more than a few small tweaks to get
everything right. Once that’s the case, collimation
is spot on.
The cool thing about these tools is
that they can be used in broad daylight.
No need for a clear, steady night and a star
test. No worry that some miniscule detail
in mirror positions will keep you from
excellent details in your observing or imaging.
No, with proper use of this LightPipe
and autocollimator, you can bet your
optics will be well aligned.
Rigel Systems USB nSTEP
Pinpoint stars, here I come. Or so I
thought. I was able to get much better
images than ever before, but they still
lacked the detail and sharpness of what I
expected. Compared to images from similar
setups, my results still looked soft.
What was I missing? I’d corrected coma
and tackled collimation, so why didn’t I
Image 2 - The AstroSystems Autocollimator is also available in 1.25-inch and 2-inch configurations.
Both are precision aligned to within 3 arc minutes.
have nice stars? To answer my own question,
I simply needed to focus.
It’s not a secret that good focus is
required to get sharp images. What is perhaps
overlooked is just how small the
range of good focus can be for some
scopes. Small for all scopes, this range of
focus gets smaller as the f-ratio gets shorter.
This means that focus becomes more
critical with faster optics. A few hun-
Astronomy TECHNOLOGY TODAY 63