If you are looking for astronomical telescopes for the first time, the chances are that you or the person you are buying it for will be relatively new to stargazing and are likely to be overwhelmed by the amount of equipment on offer.
Luckily for you, we’ve done all the hard work for you so buying astronomical telescopes can be less daunting. Read on to discover about the three main types of astronomical telescopes available today.
The refractor is the first type and takes its name from the long tubular piece of the telescope. They have their pros and cons. A refractor has the benefit of protecting delicate optics and is therefore a good bet for those who don’t want to have to be too careful about their equipment – kids for example. However, they can be bulky, may require a tripod, and are invariably more expensive.
If a refractor doesn’t sound like much for the money, then perhaps a reflector would suit you better. Using mirrors, reflectors provide great visibility but do need regular TLC in terms of being kept clean and adjustment.
Catadioptrics are the third possible option and are seen as an ‘in between’ to refractors and reflectors. They are compact and lighter, making them easier to handle.
Buying astronomical scopes doesn’t end with choosing which type to go for. You will also need to consider size of the aperture (the lens or mirror which defines the clarity of your vision through the telescope), telescope mounts and finders.
If you are just starting out, choose sensibly: go for quality and ask lots of questions. Happy stargazing!
According to the Cambridge dictionary, a telescope is described as “a cylindrical device for making objects that are far away look nearer and larger, using a combination of lenses, or lenses and curved mirrors”.
Neat as this description may be, there are distinct types of telescopes within this which we shall examine here.
Optical telescopes collect and focus light mainly from the visible part of the electromagnetic spectrum. Using one or several optical elements such as glass, lenses or mirrors, they also gather light to affect the size and brightness of distant objects.
Instruments found in this group include theodolites, spotting scopes, monocular, binoculars, camera lenses and spyglasses. Particular telescopes found in astronomy are refracting, reflecting or catadioptric; and infrared, submillimetre and ultraviolet.
As if that wasn’t enough, telescopes can also be used to measure and observe things not discernable to the eye – for example, naturally occurring radio emissions and microwave radiation from stars, galaxies and other astronomical objects. These telescopes are called radio telescopes and are built with dishes made from conductive wire mesh to collect information.
Radio telescopes are also used to search for evidence of extraterrestrial life.
High-energy telescopes make up the final group of telescopes, and they are (unsurprisingly) used in high-energy astronomy. Objects studied in this group are those which emit EM radiation of highly energetic wavelengths: black holes, neutron stars, active galactic nuclei and supernovae. Some high-energy telescopes use mirrors while some do not focus at all and use coded aperture masks, while others still have no image-forming optical system.
The Skywatcher Explorer 150P, 150PL & 200P Astronomical reflecting telescopes have today been lowered in price. The successful range from Skywatcher now represents even better value for money. The new pricing means that larger aperture scopes are even more accessible for people starting off in astronomy.
Skywatcher are just added another new product to the range of already bulging accessory list. The Skywatcher Lunar / Planetary filter set is the latest addition allowing you to get the best possible view from your telescope. Supplied in 31.7mm fitting the filters simply screw onto the rear of most eyepiece on the market and will improve on contrast and details on the major planets. The colours included and what they give you are as detailed below :
P01 Green Filter(24% transmission): Use on telescopes 8″ aperture and larger to reject blue- and red-toned structures on the surface of Jupiter and thereby increase their contrast relative to lighter parts of the disc. Also use for the enhancement of Saturn’s cloud belts and polar regions. Strongly increases contrast of Mars’ polar ice caps, and increases contrast of atmospheric phenomena on Venus. #12 Yellow (74% transmission): Contrasts strongly with blue-colored features on Jupiter and Saturn, while enhancing red and orange features. Lightens red-orange features on Mars, while reducing or blocking the transmission, and thereby increasing the contrast, of blue-green areas. Useful in increasing the contrast of lunar features in telescopes 6″ aperture and larger.
#25A Red (14% transmission): The #25A filter strongly blocks the transmission of blue and blue-green wavelengths, resulting in very sharply defined contrast between, for example, blue-tinted cloud formations on Jupiter and the lighter-toned features of the disc. Also useful for the delineation of the Martian polar ice caps and maria.
ND 96 Moon Filter(0.9 density; 13% transmission): The neutral density filter transmits light uniformly across the entire visual spectrum. It serves as an excellent filter to reduce glare and irradiation when observing the Moon with any telescope 4″ and larger. The ND96 filter may also be employed in the splitting of close double stars where one of the binary pair significantly exceeds the other in brightness.
This week promises some good star-gazing in clear night skies. However artificial lights are increasingly blotting out the stars in many places, and to find out how bad the light pollution has become we are invited to take part in a star counting study any night over the next 12 days (March 17-28). The exercise is to count how many stars can be seen in the portion of the sky around the constellation Orion. Orion is one of the easiest constellations to find and even from towns and cities its brilliant stars can be seen without a telescope or binoculars, although a clear night is needed. Further details and a form to enable to part in the annual GLOBE at Night star count can be found at here
While surfing the web today I stumbled across this great instructional telescope setup video on YouTube from ‘OrangeTube Video Studios’
This one happens to be based around the Celestron AstroMaster 90EQ telescope but many of the setup procedures are the same for Equatorial mounted scopes. Watch out towards the end of the scopes as they show how to balance your telescope tube to get the best performance out of your scope and mount.