Messier 13: Great Globular Cluster in Hercules

It was an excellent night until the moon rose but I was able to observe 4 objects tonight.

Object #2: M13
Location: Clarington, ON
Date/Time: Sep. 23, 2013 8:45 PM
Constellation: Hercules
Seeing: Excellent
Telescope: D=305 mm F=1500 mm
Magnification: 83 x @ 82° AFOV
Notes: Dark grey mainly circular ball of stars. Faint but I could resolve two “arms”. I could see individual stars in the cluster.

Messier 13: Great Globular Cluster in Hercules

On September 17, 2013, I officially started the pursuit of my Messier 30 certificate. It is an exciting awards program for astronomy club members and a way for amateur astronomers to keep track of their observations. The Messier 30 is the first milestone in‘s certificate program. The Durham Region Astronomy Association also has one.

View Updated Spreadsheet


Messier 45: The Pleiades

Object #1: M45
Location: Oshawa, ON
Date/Time: Sep. 18, 2013 11:45 PM
Constellation: Taurus
Seeing: Below average with a full moon
Telescope: D=305 mm F=1500 mm
Magnification: 24 mm @ 82° AFOV
Notes: Bright white group of stars with a hint of baby blue. Background was too washed out to resolve any wisps. Too big to fit in FOV.

Messier 45: The Pleiades

On September 17, 2013, I officially started the pursuit of my Messier 30 certificate. It is an exciting awards program for astronomy club members and a way for amateur astronomers to keep track of their observations. The Messier 30 is the first milestone in‘s certificate program. The Durham Region Astronomy Association also has one.

View Updated Spreadsheet


First Light with 12″ Sky-Watcher Flextube

My used 12″ Sky-Watcher Flextube pointed at the moon.

I took my 12″ Sky-Watcher Flextube to the Durham Region Astronomical Association’s dark site last night for the first time and found that the location was a few minutes further and more difficult to get to than Long Sault Conservation.

Moon: With a 75% full moon, it lit up the haze so much that I could not even resolve M31. So I put my shades on and observed the moon instead. The details of the moon’s surface at the terminator was spectacular. With a barlowed 7mm (428x), the image was wavering quite a bit, but so incredible. I could resolve the craters and the shadows they cast. It was like hovering over the moon in a spaceship.

Jupiter: I packed up and went to friend’s house to watch a boxing match. By the time it was over, it was already 2 AM and I could see Jupiter already. So I setup my telescope right at my front steps to observe it. At 214x, I could resolve the 2 dark stripes and at least 4 moons but again, it was wavering and not focused. At 428x, it was even worse. I was a little disappointed because the view was only marginally better than my Discovery 8 EQ.

M42 Orion Nebula: By 3 AM, I noticed Orion’s belt was higher and was above a line of haze. Still struggling with my right-angle viewfinder orientation, I pointed it in the general direction of M42 and started panning the area at 62x. It took 30 minutes and I was about ready to give up, until I noticed a glare from the corner of the FOV. I followed the glare as it got more intense, and then it emerged: The Orion Nebula.

I couldn’t believe it that even with all that haze, it was resolving with very good contrast. I noticed at least 2 round voids occupied by stars in the white dust that radiated away from the centre in 180 degree direction. I was so happy that I even woke up my wife to show it to her. Her reaction after seeing it was interesting to me: “you mean that cloud?”

My 12″ Sky-Watcher Flextube at the DRAACO observatory.

Concerns: Significantly heavier and more awkward to transport than the Discovery 8 EQ. Altitude adjustment was sticky and tube is bottom-heavy it wants to slew up quite often by itself. No significant proof of improvement over the Discovery 8 EQ thus far.

At 4 AM I packed it in. What a great ending for a mostly disappointing night.

DIY Custom Shroud for 12″ Sky-Watcher Flextube

Custom-made light shroud for my 12″ Sky-Watcher Dobsonian telescope.

Rainy days and cloudy nights make me so restless. Tonight was another one of those nights. All day, I had been thinking about custom cutting a foam sleeping mat as a shroud for my Sky-Watcher 12″ Dobsonian Flextube. But on the way home, I came up with something a little more complicated and time-consuming. A custom-made cloth shroud.

Measuring the shroud material twice and cutting once.

Step 1: I measured the inside diameter of the top and bottom tubes and the distance between them. I came up with 42.5″ diameter x 23″ height. I went to the local Fabricland and bought a thick black cloth from the clearance section ($7).

Christi sewing the edges of the shroud.

Step 2: I measured again and noticed that I had to reduce the inside diameter by half an inch to account for the thickness of the cloth. The maximum thickness allowance is 0.5″, otherwise, the material will reduce the aperture. I folded and ironed the new measurements. My wife sewed the edges for me.

Pins helped hold the folds in place while I sewed by hand.

Step 3: I taped 2 and a half lengths of velcro ($3 from Dollarama) to the top and bottom edges of the cloth and ironed them on. But by that time, my wife had gone to bed. So I had to sew the width side by hand to form the tube (the sewing machine was too complex for me).

Shroud velcro’ed to the primary tube.

Step 4: I then taped the hook side of the velcro to the inside of the top and bottom tubes and attached the shroud starting from the bottom.

Shroud partially attached to the secondary tube.

Step 5: With a little tug, I attached the top making sure it was taught all the way around. I looked through the focuser to ensure the shroud was not in the way of the primary.

Voila! A custom-made shroud just the way I like it. Tomorrow, I will be sewing the velcro onto the shroud because it is peeling off.

Hope you enjoyed this DIY.

Light shroud shown with the telescope fully extended.
Light shroud folds neatly in the tube when the telescope is collapsed.


How to Centre the Secondary Mirror by Using a Camera Phone

Today, I learned a lesson in troubleshooting a collimation problem with my new dobsonian telescope. When I took the secondary mirror off to install a washer, I could not properly get it collimated with my laser collimator on reassembly. One problem with laser collimators is that it assumes that the secondary mirror is already centred under the focuser. But that is easier said than done. Until now.

Reflection of the primary mirror’s clips are off centre.

Symptom: When I looked through the collimating cap after a laser collimation, it looked like the above photo. The primary mirror’s clips were off-centre. It was actually worse than what the photo shows. However, the photo provides a clue of what the problem may be: the secondary is not centred.

So below were the steps I took to collimate after disassembling the secondary:

Reflection of the primary tube with the cover on.

Step 1: Above, I rough aligned the secondary under the focuser and took a photo. To the untrained eye (like mine), my secondary mirror looked centred through the 1 mm hole of my collimating cap.

Using a ruler to measure the secondary mirror’s distance from the focuser tube.

Step 2: That was until I took a ruler and measured it on my screen as shown above. So I kept adjusting the secondary until both sides were equal. I pinched to zoom for more accuracy.

My refractor’s diagonal being used as a collimator.

Step 3: I used a right-angle diagonal focuser above from my refractor so that I can adjust the primary adjustment screws and receive instant feedback without walking back and fourth. I centred the donut to the reflection of the secondary.

The reflection of the primary mirror clips appearing centred.

Step 4: I replaced the collimating cap to verify alignment and it looked good as shown above. I then followed it up with a laser collimation and it still looked good afterwards.

Out in the field, I will be star testing it for fine tuning. My laser collimator was 99% true so if you plan on doing the same procedure above, check to make sure your laser collimator is properly collimated in the first place. Credits go out to the following members for helping me troubleshoot the problem: mlk1950, CamelHat, andrejl2, Jason_D

Gravenhurst Muskoka Family Star Party

Gravenhurst Muskoka Family Star Party 2013

Get ready for a family star party in the Muskoka Region of Ontario. Between Friday, October 4th and Saturday October 5, 2013, there will be a star party at the Torrance Barrens Dark Sky Site.

Organized by local astronomy clubs, it will feature a talk and slide show by prolific Canadian amateur astronomer Terence Dickinson, author of the popular book “Nightwatch: A Practical Guide to Viewing the Universe” and “The Backyard Astronomer’s Guide”.

It will be held at the Gravenhurst KOA and Torrance Barrens Dark Sky Site.

Gravenhurst Muskoka FAMILY STAR PARTY

When: Friday, Oct. 4, and Saturday, Oct. 5, 2013

Where: Gravenhurst KOA, 1083 Reay Road and TorraRnce Barrens Dark Sky Site

Featuring ASTRO TALK BY TERENCE DICKINSON followed by telescope viewing at KOA and Torrance Barrens

• 25% discount at KOA, some cabins available 1-800-562-9883, e-mail contact direct for discount

• Hotels: Mariott 705-687-6600 and Howard Johnson 705-687-7707

• Local merchant coupons for attendees • Beautiful Muskoka seasonal events

For more information, contact Alan Keates at 705-687-4364 or e-mail

Bought a used 12″ Sky-Watcher Dobsonian Flextube Truss

12″ Sky-Watcher Flextube dobsonian with upgraded GSO dual-speed focuser

Well into my first month of my astronomy hobby, and I’m already on my 4th telescope gear: a 12″ Sky-Watcher Dobsonian with collapsible trusses. Standing next to my 8″ newt, it looks like a monster scope.

The Good
I believe I got a pretty good deal with this one because it has several upgrades including:

– dual speed focuser
– stiffer primary mirror springs
– smoother azimuth bearings
– swivel caster wheels under the base

and considering these were missing:

– eyepieces
– finder scope

The condition is almost brand new, no scratches on the base, and clean and shiny exterior. The primary and the secondary mirrors have some dust on them: an indication that they have never been touched. Then again, the average astronomer take extra special care of their telescopes. The total cost was “significantly” lower than a brand new one. But it cost me extra gas because had to drive 2 hours one way to pick it up.

First Challenges
Having spoiled by my Discovery 8 EQ in convenience/performance, I have to manage my expectations in order to overcome these challenges:

Heavy: Moving the telescope from my living room to the front door was easy because it had casters. Only when I had to disassemble and reassemble it outside that I realized how heavy and unwieldy this telescope was. I was expecting this before I bought it, but not as much as this.

Decollimated: I had collimated the scope inside, but when I reassembled it outside, it had miscollimated by a quarter of an inch.

Underfocussed: The upgraded dual-speed focuser was too short and extension tube was not included. I reached focus by pulling out the eyepiece by 30mm.

Jerky Tracking: Azimuth motion was very smooth, but altitude was quite jerky and squeeky making tracking and sketching more challenging than my GEM-mounted scope that had a smooth slow motion RA.

Foreground: New new (used) 12″ Sky-Watcher Flextube dobsonian. Background: My Discovery 8 EQ on hockey pucks.

First Impressions
First light was just outside my front door where I was subject to intense glare from my neighbours’ lights and street lights. The only way for me to judge the performance would be to take it to the same dark site where I have been taking my 8-incher. I might get a chance to do that this weekend.

In about a month, I will decide which one of my telescopes will have to go.

Lin-Optics Equatorial Mount Maintenance Project

Lin equatorial mount disassembled for lubrication replacement.

My Discovery 8 EQ‘s equatorial mount is over 10 years old and it has been very ‘sticky’. It is a ‘Lin-Optics’ brand-name mount that I cannot find of any documentation on the web. Last week, I attempted to disassemble it to replace the lubrication but could not figure out how to remove the inner shafts.

This weekend, I finally had more time to look into the issue further. I needed a little bit more time to carefully figure out which set screws were meant to be removed, and which were meant to be tightened down in order to remove the shafts. It was like a rubik’s cube puzzle.

After an hour, I finally figured it out. The ascension shaft took me half as much time to figure out. I cleaned the parts with degreaser spray and wiped them clean with paper towels. If I could have collected the metal filings, I would say there was about a teaspoon of it. I then applied a generous amount of white lithium grease and put it back together.

Now, my mount is buttery smooth with the Newtonian telescope on it. It feels like I just bought myself a new mount. A fun project with long-lasting benefits.