Monday, February 04, 2008

I'm often asked about hardware, which brand, how much to spend etc, well here's my view, remember that I'm not a professional and I'm not even that experienced as an amateur compared to many many others. I have though in the last few years gone through the pain of deciding what to buy and living with the consquences.

Most people when starting out in Astronomy will usually assume that to do any useful observing you need large and very expensive instruments. I have found through personal experience that "hardware" quality and capability can vary quite amazingly.

The Skywatcher 200m aperture x 1000mm focal length "Newt" on its heavy duty motorised Equatorial mount might look very costly. The reality was a cost of around £500 in 2006 and depending on your personal circumstances only you can be the judge as to whether that is a lot of money. Of course for that money one can buy a washing machine or a Personal Computer.

If your budget won't stretch that far most peoples advice is to buy some binoculars. However, I could argue that a good quality pair of Binoculars could easily cost more than the telescope above!

I was tempted to buy some Bin's a couple of years ago but was wary as I don't have full use of my right eye, my logic was that I would be paying for two lots of optics when I could only use one. So a visit to my local "camera shop" introduced me to the Opticron brand which I had previously not heard of.

I was able to compare an Opticron spotting scope with another make and quickly decided the Opticron was better optically. So £240 poorer I left with my purchase and eagerly awaited a clear night, now, I was fortunate that in a former life I had worked as a professional wedding photographer and as such I already owned a heavy duty tripod which was instantly pressed into use.

You might be amazed to know that this scope can easily show the 4 Gallilean moons of Jupiter and if conditions are good then some cloud banding is also visble.

The scope has a zoom eyepiece (15-40x mag) and a 52mm objective lens and easily splits the double star of Albireo in Cygnus and the rings of Saturn are easily defined but don't expect to see too much detail.

A lesson learnt though is that I should have considered a larger aperture spotting scope rather than this "travel scope", at max mag the view is quite dim, ironically this is more noticeable in daylight when used for terrestrial viewing.

A later purchase acquired an Opticron 10x42 monocular which I also find needs to be tripod mounted to be of much use and is a fine instrument also.

Of course if you have a bigger budget then the sky really s the limit....

My view on what to buy is that you must consider the following....

  • Firstly - before parting with any of your hard earned cash, don't discount your most valuable asset, the good old Mark 1 Eyeball, if you let yourself get dark adapted properly and sit back in a deck chair on a good clear night you will be amazed at what you can see!
  • Cost - if you've just won the lottery then you won't care what I think because you'll just buy the most expensive kit in the catalogue, if you aren't a millionaire then get the best you can afford while considering the following.
  • Aperture - the wider the tube (OTA - Optical Tube Assembly) the brighter the image
  • Mounting - a camera tripod is fine for small scopes/bin's but at high mag's the sky appears to rotate very quickly meaning that you are constantly adjusting the scope to keep your subject in view. A motorised equatorial mount is great for keeping pace with the rotation of the earth as well as allowing long exposure photography. Remember though that once you've aligned the mount you can't move the scope around your garden without realigning it each time you move it. Also, the assembly above is very heavy, I can only just lift the assembly to move it an inch or two. So setup time has to be accounted for, several trips are needed to cart it all into position and then it needs to be assembled and aligned, although practice makes this quicker.
  • Optical quality - should really be number one but it is this which mostly impacts cost and so to most people the best optics remain out of range of our pockets. Also, I'd say that the importance of optical quality drastically increases with magnification, cheap high power EP's will be useless even on a good OTA and mount. Top of the range bin's can cost many hundreds of pounds but will show stunning detail compared with cheaper alternatives.
  • Magnification - don't expect to see the kind of views as seen in books and magazines that were taken using the Hubble Space Telescope. Also remember that long exposure photography reveals far more detail than the naked eye even on amateur scopes. Last year I purchased a low power 40mm EP for the Skywatcher which effectively turned it into a 25x200mm monocular and the view is amazing!
  • Computer guidance - sounds great, but having thousands of objects in a database is not much use if the optics won't let you see them!

To summarise, cheap optics on a good tripod will be a waste of money as would good optics on a cheap mounting. High magnification EP's reduce image brightness significantly and thus require more aperture in order for you to see anything and the higher the mag the more crucial is the mounting in terms of tracking and vibration free viewing.

Remember that "proper" scopes are like "proper" cameras, the EP's or lenses that come as standard are usually just that, basic. You can always buy better quality later, often a top quality EP or lens for a camera will cost more than you paid for the scope/camera in the first place.


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