reflector or Refractor

Fionn101

Folks, If i'm going to invest 200 or so quid into a scope should i go for a reflector or refractor ??? i want to be able to view planets and perhaps a fre binary systems ,


Any recommendations ? was going to purchase through the buy and sell as shop prices are ridiculous .


Thanks

Fionn

Flukey

You are not going to get something brilliant with €200. Shop around a bit, but first do a bit of research on the web. You'll find plenty of astronomy and telescope sites that will give you the pros and cons of reflectors and refractors. Study up on the other technical aspects of telescopes like focal length, focal ratio, the different types of mounts, lenses. Here is something I got off the net in relation to your initial question:

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Refractors are what the average person identifies with the work "telescope", a long, thin tube where light passes in astraight line from the front objective lens directly to the eyepiece at the opposite end of the tube.

Advantages:
Easy to use and reliable due to the simplicity of design.
Little or no maintenance.
Excellent for lunar, planetary and binary star observing especially in larger apertures.
Good for distant terrestrial viewing.
High contract images with no secondary mirror or diagonal obstruction.
Colour correction is good in achromatic designs and excellent in apochromatic and fluorite designs.
Sealed optical tube reduces imagine degrading air currents and protects optics.
Objective lens is permanently mounted and aligned.

Disadvantages:
More expensive per inch of aperture than Newtonians or catadioptrics.
Heavier, longer and bulkier than equivalent aperture Newtonians and catadioptrics.
The cost and bulk factors limit the practical useful maximum size objective to small apertures.
Less suited for viewing small and faint deep sky objects such as distant galaxies and nebulae because of practical aperture limitations.
Focal ratios are usually long (f/11 or slower) making photography of deep sky objects more difficult.
Some colour aberration in achromatic designs (doublet).
Poor reputation due to low quality imported toy telescopes; a reputation unjustified when dealing with a quality refractor from a reputable manufacturer.



Newtonian Reflector Telescopes
Newtonians (also known as catoptrics) usually use a concave parabolic primary mirror to collect and focus incoming light onto a flat secondary (digital) mirror that in turn reflects the image out of an opening at the side of the main tube and into the eyepiece.

Advantages:
Lowest cost per inch of aperture compared to refractors and catadioptrics since mirrors can be produced at less cost than lenses in medium to large apertures.
Reasonably compact and portable up to focal lengths of 1000mm.
Excellent for faint deep sky objects such as remote galaxies, nebulae and star clusters due to the generally fast focal ratios (f/4 to f/8).
Reasonably good for lunar and planetary work.
Good for deep sky astrophotography (but not as convenient and more difficult to use than catadioptrics).
Low in optical aberrations and delivers very bright images.

Disadvantages:
Open optical tube design allows image-upgrading air currents and air contaminants which over a period of time will degrade the mirror coatings and telescope performance.
More fragile than refractors or catadioptrics and this require more maintenance (such as collimation).
Suffer from off-axis coma.
Large apertures (over 8") are bulky, heavy and tend to be more expensive.
Generally not suited for terrestrial applications.
Slight light loss due to secondary (diagonal) obstruction when cmpared with refractors.

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Now there is loads of stuff like that on the Net, so just go and have a look. A telescope is a great thing, so it is worth choosing one carefully and even waiting instead of buying a cheap one.

Flukey

A few more links for you to try:


http://www.scopereviews.com/list.html
http://www.oldham-optical.co.uk/Astro.htm
http://www.celestron.com
http://www.meade.com
http://www.televue.com
http://www.oriontel.com
http://www.telescopes.ru