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.
There has been new pricing implemented on the Acuter pro series of spotting scopes. From today the new prices are £99, £139 & £200 on the Six models available 65mm, 80mm or 100mm objective lens diameter, and Straight or 45° viewing angle. This makes the already popular range even better value for money. Perfect for serious terrestrial observations such as bird-watching. Optical performance is excellent, with all models delivering crisp, bright, sharp, high-resolution images. The objective lenses are multi-coated for maximum light transmission and image contrast. A Zoom eyepiece is included with each model as standard, but other interchangeable fixed magnification eyepieces are available separately. Focusing is ultra-smooth and practically eliminates vibration whilst in use. The tubes are covered with a protective rubberized paint finish to help protect from the elements. All models can be mounted on a standard photographic tripod via a ¼” tripod bush. Supplied with carrying case.
Smaller, lighter and sharper, the new Opticron HR ED 80 & 66mm fieldscopes offer a host of improvements over preceding models and have been redesigned without compromise in order to deliver truly exceptional optical performance combined with sublime handling and complete reliability.Aimed squarely at the serious fieldscope user, the models are built to withstand extremes in temperature, to operate unaffected by rain, cold or humidity. Purchase either a Straight or Angled body together with an SDL eyepiece before the end of February and we will give you an Opticron 42830 Birdwatcher’s Pro Tripod free of charge.
They have been a while coming but prices for the Leica Televid have finally been announced and are shown on the website. Stock is sure to be very short for the first deliveries, so now is the time to get an order in if you have been waiting. First deliveries are due into the UK mid to end of September 08. Just to tempt you a little if you are not quite sure, we are offering a Leica stay on case with all Televids pre ordered, a saving of £150.00
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Prices, availability, appearance, product descriptions, and accessories are based on available manufacturer information and are subject to change without notice.