REFRACTOR:<\/strong><\/p>\n The refractor telscope uses\u00a0a lens at the front\u00a0to focus the light from a celestial\u00a0object. A small refractor of about 60mm\u00a0is the ideal\u00a0size of\u00a0telescope for solar observing. If you have access to something a bit larger, such as a 80 to 90mm refractor so much the better as that will on most days show a bit more detail but avoid using anything larger than 100mm. Also remember the larger the scope, the heavier it will be. The best telescope is often the one that you use the most often because it is easy to set up and use.<\/p>\n The telescope shown here is a Vixen 80mm refractor and it is mounted on a Super Polaris equatorial mounting. Both are quite old now but they work so well that I would not even think of changing them. The telescope in the image\u00a0has a full aperture solar filter fitted.<\/p>\n Eyepieces:<\/strong> If you use\u00a0the projection method then stick to using\u00a0the\u00a0relatively cheap eyepieces such as Pl\u00f6ssls or Kellners (they are still available most from second-hand suppliers).\u00a0Be aware that over time the\u00a0heat and UV from the Sun can\u00a0damage eyepieces\u00a0by making the cement between the lenses turn cloudy. If you use a full-aperture solar filter then you can use any eyepiece you like as the filter will protect the eyepiece as well as your eyes! Eyepieces such as Pl\u00f6ssls, Kellners, Orthoscopic\u00a0give sharp contrasty views.<\/p>\n REFLECTOR:<\/strong><\/p>\n A reflector\u00a0is a\u00a0telescope that\u00a0uses a specially curved mirror to focus the light entering the telescope. The light\u00a0is reflected\u00a0off the mirror,\u00a0usually at the rear of the telescope body, sending the light back up the tube to be\u00a0deflected\u00a0into\u00a0an\u00a0eyepiece.<\/p>\n Do not use reflector type telescope for solar projection as the telescope can overheat<\/strong>. Instead, consider buying a full aperture solar filter to fit over the front of the telescope. Alternatively, you do not always need a solar filter to cover all of the telescope aperture but instead purchase an off-axis<\/em> mask into which a smaller diameter solar filter can be screwed into one of the portholes in the\u00a0mask. This reduces the telescope aperture and increases the telescope focal ratio.<\/p>\n CATADIOPTRIC:<\/strong><\/p>\n These telescopes use a combination of a lens (often referred to as the corrector plate<\/em> or meniscus lens<\/em>) and a specially shaped mirror to focus the incoming light to form an image.<\/p>\n These telescope can only be used for solar observing with a full aperture solar filter with an off-axis mask (as shown here). The solar filter aperture in the image is off-centre because the secondary reflector\u00a0is in the centre of the meniscus lens at the front of the scope. If\u00a0the solar filter aperture was also central it would be blocked by the secondary effectively stopping the scope from working.<\/p>\n Never use these scopes for solar projection as they will overheat causing damage to the telescope.<\/p>\n HYDROGEN ALPHA LIGHT AND\u00a0CALCIUM LIGHT SCOPES:<\/strong><\/p>\n These telescopes are specifically made to view the Sun in the red spectral line of hydrogen. By looking (and imaging) in this wavelength of light we can see the solar chromosphere. Here we find the solar prominences, filaments and solar flares. Observing the Sun in H-alpha is not cheap but it is highly rewarding especially during periods of high solar activity.<\/p>\n There are a number of manufacturers of H-alpha telescopes. DayStar, Lunt, and Coronado are well-known brands. There is a similar scope for imaging in the blue light of calcium (CaK) also available from Coronado. These are harder to use as you have to image the Sun rather than look at it visually,\u00a0but they are rewarding if challenging to use.<\/p>\n Next: What are hydrogen alpha and calcium filters?<\/a><\/p>\n","protected":false},"excerpt":{"rendered":" There are many types of telescope but which is best for solar? Before we look at these telescopes it’s worth mentioning a bit about telescope mountings. A telescope must be firmly mounted if you are going to do any realRead more<\/span><\/a><\/p>\n","protected":false},"author":17,"featured_media":0,"parent":1643,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_monsterinsights_skip_tracking":false,"footnotes":""},"categories":[],"tags":[],"class_list":["post-1650","page","type-page","status-publish","hentry"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t![\"telescope](\"https:\/\/www.popastro.com\/solar\/wp-content\/uploads\/sites\/11\/2017\/01\/telescope-on-equatorial-mounting.jpg\")
![\"a](\"https:\/\/www.popastro.com\/solar\/wp-content\/uploads\/sites\/11\/2017\/01\/396px-150mm_Texereau_telescope_n1.jpg\")
![\"solar](\"https:\/\/www.popastro.com\/solar\/wp-content\/uploads\/sites\/11\/2017\/01\/Mak-with-an-offaxis-filter-mask.jpg\")
![\"Coronado](\"https:\/\/www.popastro.com\/solar\/wp-content\/uploads\/sites\/11\/2017\/01\/PST-Ha-Telescope-jacs-cropped.jpg\")