My amateur telescope
The "Deep Space Scope"
Home | Astronomy | DS-3 |
Results under the stars
Results - abstract
DS-3 was more successful than my wildest hopes. It is a
that rivals any other scope that I have tried in it's size, always
draws a crowd, and easily fits in my car. It is also easy to
carry and doesn't take up much space for storage. Images are
fabulous, and it is easy to use. It was also reasonably easy
make, and fairly cheap.
Results - Details, working top to bottom
- Setup/ tear
down - Setup
takes under 5 minutes. 1) Pull scope out of the car, place
it goes. 2) Remove secondary cage. 3) Drop in
trusses. 4) Attach secondary to trusses. 5) Columnate ( 6
Possibly attach baffling.) 7) Attach
Quickfinder. Tear down is also under 5 minutes.
- has ended
up working very well. Objects are easy to find. The
quickfinder is out of the way as placed on this telescope.
- 2" KineOptics
- This focuser is not bad to use. It goes from totally in to
totally out in about 1 3/4 turn. It moves from totally in to
totally out in about 1 1/2 inches. If you are careful, it
still has enough precision
to make it easy to focus. I do wish it had finer resolution.
Workmanship is fabulous. It is
quite light weight, although I am not sure exactly what it weighs.
- Upper "cage"
This has worked out fairly well. I like the design of my DS-4
scope better. The 1/2" plywood ring is plenty
stiff, and very light. The wire spider has generally worked
very well. The only four things that have been issues with
spider are: 1) the nuts on the brass rods sometimes loosen.
with some locktite. 2) The wire, as it runs through the brass
rods, sometimes moves if you pull on it, thus messing up
columnation between observing sessions. Not yet done, but
solution - push a toothpick in the
hole in the brass rod, and put a drop of CA glue on it. The
will never slip again. 3) As you adjust the columnation
the secondary, the whole secondary mount rotates in space, stretching
the wires. Until you let go again, letting the wires spring
to their original position, you have no idea if you went enough, or
even if you are turning in the right direction. Makes
take longer. Defraction spikes that do exist are in a pretty
pattern. Conclusion - after getting the secondary columnated,
unconventional upper cage works quite well. If I ever rebuild
secondary cage, I will probably use a DS-4 design. See
"Astronomy" above, then select "DS-4.
- 3/4" trusses
are working very well. There is no
backlash at all as you are moving the scope. Columnation is
solid, no matter what the orientation of the scope. (See
cell below.) Adding wide black electrician's tape has helped
looks, baffling, and to make it more comfortable to move the
scope. I find that I generally move the scope by grabbing a
and dragging it around. The truss attachments have worked out
very well. They never slip, are easy to make, and have held
well. When putting the scope together, it does take a few
and a bit of experience to get the tops of the truss tubes lined up
properly. One issue that I am working on is where to place
three upper truss connection nuts when I am setting up/ tearing
down. They keep getting put in a pocket and
option is to install three very small screwed rods hanging off of the
- Mirror box
- This has
worked out very well. Relatively light weight,
and a bit of a dust barrier.
bearings - These
are right at the edge of not being sticky enough. Taking a 1
eyepiece on/off the scope makes it go from almost too heavy to almost
too light. I have some weights I take with me to help balance
upper cage (which is too light). Movement is smooth and
- Mirror cell
- The mirror
cell has worked like a charm. It stays in columnation no
what the orientation. I have driven the scope up to 381 power (8mm
Orion Superwide Lanthanum with a 2X Televue BIG barlow), and could see
NO astigmatism at all, no matter what the orientation. The
cell also probably cools the mirror down about as fast as is possible
without a fan.
- Mirror cooling
- The Aire
rings around stars never did stop slowly waving, making me believe that
I have surface layers on the mirror. Next project - a fan
will be velcro'd onto the top of the mirror box.
- Rocker box
These have worked perfectly well, giving NO backlash (or bending) when
adjusting the scope. I am becoming suspicious that I actually
over did the stiffing of the rocker box, and thus wasted
Next time, I won't add the stiffening boards until proven that I need
- Vibration -
has no vibrational issues at all, unless there is a pretty strong
wind. Even then, this scope is generally the last truss
still standing at the end of the night.
- Baffling -
section on baffling here.
- Build cost
- was under
$1000. (I didn't keep receipts, so don't know how much under
$1000 it was.)
Results - star tests
- I am a bit of a new observer with really good equipment, so
probably not the best person to give a final rating to this
scope. But, since I am all I have, here goes.
- The scope is sensitive to Columnation. When
right on, stars are pinpoints using any eyepiece that I have, including
my 8mm. With exceptional seeing, using a 2x barlow and my 8mm
eyepieces (giving 4mm) works acceptably well with Saturn.
- With good seeing, the 6 stars of the trapezium are obvious,
are viewable with direct vision.
- The double double stars in Lira are splittable, and I can
thin dark lane between
- I could not see the center star of the Ring nebula.
- In medium dark skies with GOOD seeing, I could almost, kind
guessing, while moving the scope, see the darker area of the horsehead.
- Saturn was amazing! The Cassini division was
constant, just sitting there with direct vision. Both inner
outer ring graded from bright to gone as you worked your way away from
the division mark.
- An observer here commented "beautiful views" after looking
Saturn, then returned to his 20" binoviewer scope. (As an
this 20" binoviewer scope knocked the socks off of anyone, including
me, that looked at anything. Those views definitely put me in
place! Saturn was absolutely alive through that scope.)
- Star tests look very symmetrical around the
center. As I
rack in/rack out, one side of focus is fuzzier than the
notice this on ALL scopes that I look through, so wonder if it is my
eyesight. The other option is that I have a bit of a turned
edge. I will try it with a mask one of these days.