New Equipment Review – William Optics Zenithstar
66 SD:
By
Clayton W. Kessler
Seven
Sisters Observatory –
Manchester
Michigan
February
2007
Some of the clouds lately have been my fault.
At the FAAC Swap and Shop I took delivery of a small
APO
refractor made by William Optics – the Zenithstar 66 SD.
For the last several weeks I have been using it as an astrograph in
concert with my modified Canon 10D DSLR. I
can honestly say that I have never owned a better behaved little scope!
Product photo from manufacturers web site
This is an interesting little scope that uses an ED glass doublet to
achieve very good color correction. I
suspect it has a big following with owners of large Meade and Celestron SCT’s
as a very high quality finder – it is available in Meade blue and Celestron
Orange and has SCT style threads as an attachment on the focuser.
This is kind of nice as you can use your SCT accessories with this little
scope. The scope is a 66mm f5.9
scope providing 388mm FL. The
doublet uses an FLP51 glass element as the ED element and the color correction
is very good to my eye.
I was able to easily mount the scope on a tripod and look through it on
the evening that I brought it home. Weather
conditions were not the best but a star test showed good round diffraction rings
on either side of focus. Saturn was
sharp and color free on the edges. The
most impressive thing about this first look was the very tight star images.
Several moons of Saturn were visible as very tiny specks around the
planet.
A week or so of poor weather followed and I was unable to do more than
look at “stuff” in the house. With
a 2” SCT diagonal this scope becomes sort of a long distance microscope able
to focus to about 12 feet away. Images
were again very clear and free of color fringing.
I was becoming very happy with this little gem.
Speaking of gems – I should mention the fit and finish of this scope.
It has a retracting lens shade that brings the scope length from 14.2”
to a very transportable 11.8”. It
comes equipped with a 1.6” crayford style focuser that features a 10:1 speed
reducer on one side. The focuser
also rotates to aid in composing a photograph and has a focus lock and a tension
control. The focuser is butter
smooth and easy to use. The focus
tube has an etched distance scale to aid in rough focusing a camera.
The anodizing of the tube and focuser is second to none!
The scope is hefty for its size and everything about it screams quality.
Lens coatings are the WO “STM” full multi-coating and the glass just
seems to disappear when you look directly at it.
There are 10 baffles in the tube that is really a single piece with
pointed areas on it’s inside diameter.
It seems to do the job so far. The
focuser has a built in heavy duty bracket for attachment to a tripod.
The included 1.25” adapter has a nice brass compression ring to hold
eyepieces and such. The scope even
comes packaged in a nice aluminum case with extra room for accessories and
eyepieces. The best part…. All
this for $299.00!!!!!
Now – all you guys know that I seldom LOOK through a telescope
preferring to hook up a camera and take astrophotos.
Knowing I would be taking astrophotos I sprung for the .8 focal reducer /
field flattener to assure that my DSLR would have nice sharp corners.
In the last couple of weeks I was able to take the sub frames for three
astrophotos through this scope. All
were taken with my modified Canon 10D, on my G11 and guided by my ST4.
The first shot is old faithful M42. I
took 6 five minute exposures for the main part of the shot and I “feathered”
in several shorter series of exposures to eliminate the burned out area around
the trapezium.
The
next target a week or so later was M45. I took 9 three minute exposures and 4
five minute exposures with 2 three minute dark frames and 2 five minute dark
frames. Deep Sky Stacker combined
the images and my old copy of Photoshop 4 took care of the final tweaks.
I have had a lot of trouble shooting M45 and getting the detail that I
know is there. I was very happy to
see how this little scope handled this cluster.
The
same night I moved the scope over to NGC1499 and shot 11 five minute exposures
and combined them with 2 five minute dark frames.
I am pretty happy with the result as I think I got a
LOT
more detail than my best film
shot of this object.
All
in all I am thrilled with the performance of my first
APO
.
I can hardly wait to try the Rosette with this scope and M31 should
easily fit the FOV. I am looking
forward to the summer milky way when I can shoot the North America Nebula, the
Lagoon and all the nebulosity around Antares.
I
can recommend this scope without reservations to anyone that wants a small high
quality
APO
refractor.
If you want to look at one come on out the Seven Sisters Observatory in
Manchester
some clear evening or head on over the Riders Hobby Shop in
Livonia
.
John Kirchoff keeps a sample in stock there.
I must admit it is rather nice to be able to buy a scope like this
locally!
I am sold on
APO
’s.
They really make it easy to take some pretty good astrophotos.
Now I need to save my pennies for a 90mm
APO
….
Hmmmmm… they even make a 132mm version……