last updated  February 13, 2001
Astronomy in the Great White North !

My name is Juan. I live in Gatineau, Quebec.  And I have an small observatory 100 Km North of Ottawa.
This page is mainly dedicated to  Astronomy under extreme cold.  Mel Bartels telescope control system.
And other bits and ends.

Nov. 10,  2007

After a  six year hiatus from Astronomy because I joined  rock band.
(Video of the group, I'm the one with the white hat)

 I'm back !

And I'm upgrading the telescope to servo control. So I'll be updating this pages soon.

Observing during  extreme cold conditions is quite a trip!
The observatory lies 200 feet from the shores of  Lac du Moulin.   At -20C. Your can hear the lake's ice crack. The cracks always run from East to West and take about 4 seconds to cross the 2 Km lake.  At -30C. The tree trunks also start to crack and it sounds like 410 caliber gun shots. Add the echo from the surrounding hills, the cold, and the stars.
And it becomes a mistical experience.

Last fall I embarked on Mel Bartels telescope drive adventure.
It consist in a sophisticated stepper motor control program. That can convert any telescope into an accurate GOTO instrument.
Given the rigors of Canadian winters and the fact that the scope sits in an unheated observatory 100Km from home. I had planned on assembling the project at a leisurely pace at home during the winter months. And then. Installing the system on the German mount at the observatory come spring time. There was no way that I was going to be caught tapping screw holes on metal in sub zero temperatures !... 

Tapping screw holes on metal in sub zero temperatures is really not that difficult  (if you are crazy enough).
That's right...I could not wait any longer !.The system was ready. I had done all the bench testing that I could imagine. And I could not wait any longer  to see the system  work !. So last  January.  I went for it

the mount    ra drive     DEC drive

        The mount                       RA drive                    DEC drive

Getting there is half the fun !This has been a very mild winter. But as luck would have it. A cold snap decided to bring the temperatures down to -30C on Friday and -35C on Saturday !  The observatory is on top of a hill, at the end of a 1000 foot trail through the woods. Normally. Transporting  all the equipment ( 2 desktop PCs, monitors, tools, etc.) would have been easy with the help of my small four-wheeler. But due to the extreme cold. I could not get the darned thing started. So I had to snow-shoe all the equipment up to the observatory by pack sac.

 But Hey !    What are we ?     Nerds ?

The installation actually went quite well ( I did not loose too many fingers). The only accident occurred when one of the Plexiglas boxes that I had built to cover the gearing mechanism. Fell off the edge of a chair. The face plate shattered as if it was made out of glass. Plexiglas don't flex too much at -30C.

While setting up the connections for the ST-4. I placed a mini screw driver between my lips...
INSTANT SEAL!!! I'm sure I won't repeat that one again... this winter!
(picture not available)

The observatory

Last summer. I installed a quality  sound  system with home made speakers  (my other hobby). Suddenly seeing took a beat. All stars had become pulsars. The low frequency sound waves  were making resonate the large sonotube scope. You can actually stick your head in the scope and hear the base get amplified, some frequencies worst than others.
So here I am. Stuck with a pair of high end 10" woofers. Powered by a Denon system. And being forced to listen to it. No louder than a clock-radio. GRRRH....!

            Roof opening mechanism

Sliding weights on both the opening and closing wires are a must
in order to always maintain wire tension for smooth winch operation.

Why I don't suffer from differential flexure

The guide scope mount is made of oak and is extremely rigid in all axis.
My design philosophy was simple.
Not only should the guider mount not depend on the main tube for strength.
But it should actually add strength to the main tube.

A good focuser mounting platform will not only  reduce flexure.
But  will also allow for easy critical adjustment of the focuser in all axis.
And as in my case. Solve vigneting problems.( The hole through the platform and the scope tube is now 3.5" diam).

Four aluminum straps tensed and bolted around the main tube. Provide further antiflexsure support. One at the mirror cell. Two at the scope cradle / guider mount  intersections. And one at the spider mount. The later allows to tense the spider vanes at levels that would otherwise deform the tube into an square.


The above shot of M13 was taken with Mel Bartels  free telescope control program. As you can see. It is capable of very accurate tracking. But what is really fun is to click at an object on my PC planetarium and see the big telescope majestically slew to it with pin point accuracy. 

50 minutes film exposure tracked  with guidescope

(for those that accuse cardboard tubes of flexure)



(click to enlarge)

One last detail !
Some of you might be wondering how I can tough the unbelievable cold during those long observing nights....
Simple ! I use my electric astro suit.
Take an electric blanket and rip out the heating wire. Run it  through the lining of a one piece snow suit.  Et voila !
So maybe I'm not really so tough  ; )

Extreme Astronomy Yahoo group  (I'm not the only crazy one!)

SiTech servo motor, telescope control systems
SiTech Yahoo group

Mel Bartels  stepper motor, telescope control system
Mel Bartels Yahoo group