Observatories) tend to be pointed at small areas for short periods because Probes (and for that matter of Hubble and professional Earth-bound To notice big things happening on the planets. Might think that, given all the probes out there, that NASA would be the first Wield left by Shoemaker-Levy on Jupiter with my old C8.Īgain, a view of Saturn on a fine night through a big scope is just Something really dramatic happens, like the impact ofĪ comet into Jupiter which has happened twice in the last few decades and leftĭark marks visible with even a small telescope: I vividly recall seeing the New white spot (the original was found by an amateur – Will Hay). More stable, but the rings change angle and you might be lucky enough to see a Position, occult and show shadow transits. Has frequent changes in its cloud belts and spots, whilst its moons change Mars periodically suffers globalĭust storms which blot out all surface detail. The ice caps grow and shrink with the seasons. Mars hasĬlouds and dust storms and the albedo marking show subtle variations Whilst the planets change in a way stars and deep sky objects do not. It is a constant challenge to pick out and perhaps sketch planetary detail, Then someone a few years imaged flashes from meteorite impacts… Unchanging reporters of “Transient Lunar Phenomena” were regarded as cranks. People used to think the Moon was static and Moon has an endless array of interesting detail and is a whole other world ofĪnd rays to explore. In fact, the Moon and planets make fascinating subjects for both the Makes me laugh because it is an attitude hangover from the middle of lastĬentury when planetary astronomy was making no progress and was deeply out ofįashion. To some this is the hallmark of a newbie, which always Main (though certainly not only) interest in Astronomy is and always has been Personally I wouldn’t recommend one as your first/only refractor as they are quite specialised although I have had some lovely lunar and double star views with both scopes.Astro Physics 130 EDT – an absolute planetary classic. They also only have 1.25” focusers so the maximum field of view in the f15 would be about 1.3 degrees, vs around 3.8 degrees with a 40mm 2” eyepiece in the f7. They have a long focal length and slow focal ratio, with well figured optics so are good planetary and lunar and double star scopes, but don’t have the widefield capability you would get with a 100mm f7 for instance. They are actually exactly the opposite of what you said ie they are dedicated visual instruments, not really suited to astrophotography at all. I actually have both of these on trial from FLO at the moment. These created a bit of a buzz on the forum, when they appeared at Auntie I ask what would they be suitable for visual observing, or just for astrophotography? They make excellent all round instruments, but as with all telescopes, as well as having wonderful attributes, they have their limitations. The beauty of the ED or apo doublet is that it can often take higher magnification on such things as the Moon, and double stars due to no or virtually no chromatic abberation. For many seasoned lunar & planetary enthusiasts a good 4" refractor may well be prefered to a 6" or even an 8" reflector due to their sharp imagery and ability to often be relatively unaffected by poor seeing conditions. I would consider a 4" to 6" F5 to F8 achromat to be a serious visual instrument.įor lunar & planetary I'd prefer an Apochromatic or ED doublet refractor, again between 4" to 6", but the costs increase because of the exotic glasses used in manufacture. When considering a refractor for such tasks their being achromatic isn't such a big issue, as chromatic abberation isn't nearly as noticeable on such targets as it is on the Moon & planets. Depending on the aperture you're considering, they can be excellent for brighter deep sky and comet seeking. Most definitely! Refractors are renowned for their exquisitely sharp, tight star images, and that makes them virtually unbeatable for viewing wide, rich star fields.
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