BIG TELESCOPE DRAWING SERIES

For example, I've found yellow filters especially effective for viewing the low-contrast south temperate ovals. The Wratten 8 filter is especially effective as a general-purpose contrast enhancer.Įxperimentation is the best way to discover which filter works best with a given Jovian feature. I like to use yellow filters such as Wratten 12 (medium yellow) and 8 (light yellow) to enhance the contrast of the polar regions. Red filters such as Wratten 21 (orange-red), 23 (light red), and 25 (red) can be used to enhance bluish features, such as the projections and festoons often found on the southern edge of the North Equatorial Belt. For example, the Great Red Spot (GRS) and reddish brown belts are best seen with blue filters such as Wratten 82A (light blue), 80A (medium blue), or 38A (blue). As a general rule, choose a filter with a color opposite that of the feature you want to observe. Many serious planetary observers prefer high-quality Plössl or orthoscopic eyepieces to complex models designed for ultrawide-field views.Ĭolor filters that screw into eyepiece barrels can improve the contrast of certain Jovian features and assist in identifying them. As with the telescope itself, the eyepiece too must deliver sharp, high-contrast views. I find that my 8-inch is limited to about 200x on nights of steady seeing. Consequently, you will rarely use more than 40x per inch of aperture. Says McAnally, 'I pay very close attention to the telescope¹s collimation, which really makes a difference in being able to see subtle detail on Jupiter.'Īlthough Jupiter is big and bright, it doesn't tolerate high magnification well - the image tends to go soft quickly. McAnally is seen here with his 8-inch Schmidt-Cassegrain telescope, the instrument he uses for most of his Jupiter observing. Larger instruments will allow scrutiny of fine detail and subtle low-contrast markings. A well-made 5-inch refractor or 6-inch reflector on a sturdy tracking mount is really about the minimum for serious Jupiter observing. Regardless of telescope type, the optics should be perfectly collimated. The truth is, the 'best' telescope is one that you use rather than an ideal one that you don't use. Telescopes with contrast-robbing large secondary mirrors, such as Schmidt-Cassegrains or Maksutov-Cassegrains, have been considered less desirable, but their central obstructions can be more than made up for by large aperture (assuming the optical quality is high), and many of these scopes have produced impressive results in recent years.īut no observer should put off observing Jupiter for lack of the perfect telescope. Next comes telescope type the best planetary scopes have traditionally been apochromatic or long-focus achromatic refractors and long-focal-length Newtonian reflectors. Right up there too is top-notch optical quality. First and foremost, this means large aperture. Equipment Mattersįor planetary observations, what telescope is best? The answer is simple: the one best capable of giving sharp, high-contrast views. All it takes are determination and the effective use of equipment you may already have. Jupiter has been called 'the amateur's planet,' because it offers a wealth of opportunities for amateur observers to make contributions to planetary astronomy.

BIG TELESCOPE DRAWING SERIES

The series advances in rotation by approximately 25° of Jovian longitude per image. One complete rotation of Jupiter can be seen in this CCD sequence obtained from December 1999 through February 2000.

Big telescope drawing