Archive for the ‘Uncategorized’ Category

Review of the SkyWatcher SupaTrak Auto Tracking Motorised Alt Azimuth Mount

Wednesday, April 28th, 2010

I bought my SkyWatcher Explorer 130P telescope in March 2009, so I’ve had it for just over a year now (April 2010). One of the reasons I opted for this particular telescope was because it had a motorised mount. I knew nothing about mounts (or telescopes for that matter) at the time so I based my choice on what I had read on the Internet.

Am I pleased with the mount? well, kind of. In this post I’ll share my thoughts on what I like, and dislike, about it.

Good Points

1. Physically connecting the mount to the telescope tube and the tripod is very straightforward and can be done within a minute or so.

2. Setting up the software is also fairly easy to do. There is a one-off  task to set up the latitude for your location, which only needs to be redone if you use the telescope several miles from where the setup is done.  

3.  The setup process for each viewing session is simply a case of switching on the power supply while the telescope tube is horizontal and pointing north. 

4. Tracking objects works well so long as you have carried out steps 2 and 3 above accurately.

Bad Points

1. The battery pack does not have an on/off switch, meaning that you need to use the thumb screw to connect it to, and disconnect it from, the mount.

2. The mount has two servo motors: one for altitude adjustment and one for azimuth (horizontal) adjustment. I find that the azimuth motor seems to struggle sometimes, even when the batteries in the battery pack are new. The problem seems to be worse in the cold weather.

3. My handset broke after I had had the telescope for 11 months (see http://www.myastronomyblog.com/?p=269 for more information).

How many telescope eyepieces should I have?

Wednesday, April 14th, 2010

When I bought my SkyWatcher Explorer 130P telescope it came with two eyepieces (25mm and 10mm) and a Barlow lens. The focal length of the telescope is 650mm, giving me the following range of magnifications:

Eyepiece Focal Length Gives a Magnification of With Barlow Lens (2x)
25 mm 26x 52x
10 mm 65x 130x

(Formula to calculate magnification is: telescope focal length / eyepiece focal length)

My initial thought was that I needed to rush out and buy a 4mm or 5mm eyepiece to crank up the magnification to 260x or more (using the Barlow lens), and I have to admit I did do this – well I bought a 5mm lens anyway.

And to be honest, I’m not sure it was really worth it. Focusing at 260x magnification is quite difficult and I find that most of the time I don’t go any higher than 130x, which I can achieve with my 10mm eyepiece and the Barlow lens.

Recently I bought a 40mm eyepiece, giving me magnifications of 16.25x and 32.5x. This, I get a lot of use out of because it’s really easy to find objects using it and it gives me a wide field of view.

So, in conclusion I would think very carefully about whether you really need to buy eyepieces that give high magnifications as you’ll probably do most of your star gazing at fairly low magnifications.

Problem with my SupaTrak Alt-Azimuth Mount

Monday, February 22nd, 2010

On Saturday (20th Feb, 2010) I was eagerly looking forward to taking a few more photos of Orion, but I had a nasty surprise when my SupaTrak Alt Azimuth mount refused to play ball.

When I switched on the handset/motorized mount, the Set and Go Cruise buttons starting flashing, and they wouldn’t stop. This rendered the the motorized mount useless as it refused to do anything.

Having put a post on a forum, it looks as though there might be a communication problem between the handset and the mount.

I bought my telescope (a Sky-Watcher Explorer 130P) just under a year ago, so it should still be under warranty if I need to return it. I hope it doesn’t come to that as I don’t want the hassle.

So, it looks as though for the time being I’ll have to revert to my 50mm reflector telescope … oh hum …

Update – 23 February

I put another post on a different forum, again asking the same question and, yes, it looks as though it is a communications problem between the handset and the alt-azimuth SupaTrak mount.

This morning I received an email from Telescope Planet asking me to return the handset. Hopefully, it is that rather than the mount, which would cost a lot more to send through the post.

Update – 04 March

Well, I’m still without a handset, so in effect I’m still without a telescope ! We’ve had some really clear nights recently as well, so it’s all a bit frustrating …

Update – 08 March

Still no word from Telescope Planet … and we’ve had some really clear skies just recently.

Update – 13 March

Today I received a new handset from Telescope Planet … but the problem still exists. I’ve sent another emal to Telescope Planet asking them what to do next. It’s looking as though the mount will need to be replaced.

Update – 18 March

I’m still without a working telescope. I feel frustrated at the moment because, although they are always very polite, I always feel that there is a lack of information from Telescope Planet as to what they are doing to resolve my problem.

I’m also aware that the nights are becoming lighter and I’m losing valuable astronomy sessions while my telescope is broken. I’ve also started looking at alternative telescopes – just in case I end up having to buy a new one. I need this situation with my broken scope to be resolved by the end of the month (March 10).

Update – 23 March

I’ve received an email from Telescope Planet asking me to package up the mount and handset so that they can be sent to the manufacturer for testing/repair. It feels a bit like pulling teeth, but I guess we’ll get there in the end.

Update – 30 March

Today I posted the mount, power supply pack and handset off to Optical Vision (the suppliers to Telescope Planet) so that the unit can be tested and, hopefully, fixed. I guess I just have to wait now.

Update – 08 April

I contacted Optical Vision today to see if they had made any progress with my ‘mount’ problem, but it was still waiting for a technician to test it. They rang me back later though to say that they had tested the mount and it was OK. They spoke to my wife so I’m not sure what was said exactly, but they’re returning everything to me – with another new handset (see 13th March entry above – I’ve been here before).

Anyway, everything should be with me by Monday (it’s Thursday today), so we’ll see.

Update – 16 April

Success – yesterday I received my mount, handset, and battery pack back from Optical Vision, and everything now works OK. The handset has been replaced so that must have been the problem (the replacement handset that Telescope Planet sent me a while ago must have been faulty).

So, in conclusion, a successful outcome even though it has taken eight weeks to resolve the problem. Everyone I have dealt with at Telescope Planet and Optical Vision has been very polite and helpful, although I have been frustrated sometimes by the slow progress.

Observing the Orion Nebula – Messier Object 42 (M42 / NGC 1976)

Saturday, November 28th, 2009

Date:  25th November 2009
Location: Weston, Hitchin, UK
Time: 10:30pm
Equipment: 10×25 binoculars and SkyWatcher Explorer 130P telescope

The Orion Nebula (also known as Messier 42, M42, or NGC 1976) is a diffuse* nebula situated in Orion’s sword (or dagger), south of Orion’s Belt.

It is one of the brightest nebulae and, having a magnitude of 4, is visible to the naked eye in the night sky (in reasonable viewing conditions). In my back garden, I could just about spot a small fuzzy smudge without using binoculars; with binoculars, I could see a slightly larger fuzzy smudge!

The Orion Nebula - M42

Being in the Orion constellation, M42 is very easy to find – there’s no need to do any star hopping with this one – basically, you just look up and there it is. Orion’s belt is a very easy arrangement of stars to identify.

Distance

M42 is located at a distance of 1,344 (± 20) light years and is the closest region of massive star formation to Earth. The M42 nebula is estimated to be 24 light years across. It is sometimes referred to as the Great Nebula in Orion or the Great Orion Nebula.

The Orion Nebula - M42

Telescopic View

I have to say, I was quite impressed with the view through my Sky-Watcher Explorer telescope.

With previous Messier objects I have observed, I could only really make out that there was a fuzzy smudge and not much else, but with M42, I could see quite a few stars that had formed within the nebula, as well as being able to identify an area of dust and gas. Basically, there was some shape to the object I was observing.

And there was certainly no need to crank up the magnification very much. I eventually settled on a magnification of 130x, but 65x would have been fine.

Betelgeuse and Rigel

As we’re on the subject of the Orion constellation, it makes sense to mention a couple of big, bright stars that reside there: Betelgeuse and Rigel.

Betelgeuse

Betelgeuse is a variable star located approximately 640 light-years from the Earth. It is the second brightest star in the Orion constellation and the ninth brightest star in the night sky. Rigel is usually brighter, but as Betelgeuse is a variable star (its magnitude varies between 0.06 and 0.75), it is on occasion brighter than Rigel.

Betelgeuse is a red supergiant, and one of the largest and most luminous stars known. It has a luminosity about 13,000 times that of the sun, and if it were at the center of our solar system its surface might extend out to between the orbits of Mars and Jupiter, wholly engulfing Mercury, Venus, the Earth and Mars.

Astronomers believe Betelgeuse is only a few million years old, but has evolved rapidly because of its high mass. Some astronomers believe it may become a supernova within a timeframe where it could be observable by human civilization.

Rigel

As stated above, Rigel is (normally) the brightest star in the Orion constellation, and the sixth brightest star in the sky, with a magnitude of 0.18.

Rigel is a Blue supergiant, and shines with approximately 40,000 times the luminosity of the Sun. It is about 700 to 900 light years from Earth.


* Diffuse nebulae are clouds of interstellar matter, namely gas and dust. If they are large and massive enough they are frequently places of star formation, thus generating big associations or clusters of stars.