Observation report: first light 160mm Gajdusek-Kozelsky refractor & the Fullerscopes MK IV

Spring in November.  That's the actual weather in Belgium. 
Very strange weather.  Mosquitoes in November...

Result of this warm weather is a lot of dew and fogging.  Not the best observation conditions.
A good dew controller is needed.


The 160mm f:15 Gajdusek-Kozelsky refractor is installed in the observatory on the Fullerscopes MK IV equatorial mount.  Tracking and GOTO is now possible.  The Fullerscopes MK IV is a classic heavy duty mount retrofitted with stepper motors and an FS2 controller.

The Gajdusek-Kozelsky refractor is originally mounted on the original altaz mount.  

It's only a 16cm refractor but it's an impressive heavy telescope.Steel tube with balance weights inside the tube.

With a length of 240cm and a weight of +/-30kg it's the limit for the MK IV.  But the system works very smooth.

The focuser is a nice oversized 2" rack and pinion.  Very smooth.  Perfect for fine focusing at high magnifications.

The zenith prisms are an original 30mm made by Kozelsky and a 2" made by Zeiss.

Observation report

First views were very disappointing.  Blown up stars and a very bad star test. Almost impossible to focus the image.  Compared the images with the views from the 10cm Polarex.  Pinpoint stars and almost textbook star test.

After 45 minutes the Gajdusek-Kozelsky was cooled down and ready for the real work. Pinpoint stars!
First object: Aldebaran.  Red giant.  Perfect colour and deep black background.  Started with a 50mm 2" Rini eyepiece.  Pushed the image to 400x with an Abbe Zeiss 6mm ortho eyepiece.  Dimmer view but almost no colour aberration.  A little green border.  Up to 300X no trace of false colour.  Remarkable result.
Enough technique.  Time to enjoy deepsky objects.

The pier of the Fullerscopes is made for the 30cm Cassegrain and not for a long tube refractor.  Not the most comfortable observing position.  So limited to lower situated objects. The pier should at least be 75cm higher. 

First deep sky object were the Pleiades, open cluster in Taurus.  Pin point stars.  The field of view is to small to observe the complete cluster.  Bud large enough to see the three triangles.

Of course the Orion Nebula.  Low at the horizon just above the houses.  Nice fit in the 31mm Nagler.  Compared to the 4" Polarex much more detail.
A long tube refractor is excellent for faint stars.  Challenge to observe the E-star (mag 10.3) in the Trapezium cluster inside the Orion Nebula.  Could easily see the E-star.  Not possible with the Polarex.

The three open clusters in Auriga were the next objects.  Already higher in the sky.  Not so easy to observe.  Seated on the ground of the observatory.  Beautifll.

The back to Orion for double star hunting. Beta Orionis or Rigel was an impressive split.  Already visible with the 31mm Nagler but best with a Circle T 12.5mm Ortho

The Quadruple of Sigma Orionis was very interesting.  The seeing wasn't longer good.  Could only see the C-star with averted view.  Same with the C-star of Struve 761.

Last object was the open cluster M35 in Gimini.  I always compare M35 with an open hand full of shiny diamonds.   The companion cluster NGC2158 was visible, faint, only with averted vision.

Ended the observation session at 4am...

It was a great night.  Enjoyed a lot the 160mm Gajdusek-Kozelsky refractor.  Would it be with the 20cm (8") refractor?

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