Senin, 29 Juni 2009

my stellar seeker (astromaster 90EQ)


ga sabar nunggu ni seeker, biar ga trus2an half naked watchin those poppin star hihih...

captain cpet ambil hardcasenya!!! 

hihi sedikit perkenalan ttg my lovely SS28

SPECIFICATIONS
   
OPTICAL DESIGN  = Refractor
APERTURE  = 90 mm (3.54 in)
FOCAL LENGTH  = 1000 mm (39.37 in)
FOCAL RATIO = 11.11
EYEPIECE 1 = 20 mm (0.79 in)
MAGNIFICATION 1  = 50 x
EYEPIECE 2 = 10 mm (0.39 in)
MAGNIFICATION 2 = 100 x
MOUNT = CG-3 Equatorial
OPTICAL COATINGS = Multi Coated
WEIGHT = 23 lb (10.43 kg)

kenapa pilih refractor??

The refractor is what most people think of when you say “telescope” – a long tube with a lens at the top and an eyepiece at the bottom. A refractor has the advantage of being an unobstructed optical system. Unlike other designs, there is no small mirror at the front of a refractor to block incoming light and scatter it into the image, so a refractor’s contrast is better than other telescope types. Refractors also require less maintenance, particularly collimation (keeping the scope’s optics aligned for the best images). They are more tolerant of temperature changes when the telescope is taken outside, so they deliver good images without having to wait for the optics to cool down, as with a reflector. 

Given favorable seeing conditions, a modestly-sized refractor can show you lunar and planetary features with better contrast range and more detail than any other telescope type. This is especially true on nights of less-than-perfect seeing, when the details visible in a larger scope are often blurred by turbulence in our atmosphere. A smaller refractor looks through less of our unstable atmosphere. Its images are consequently less affected by this turbulence. A good 80mm refractor, for example, can reveal more lunar detail than you can sketch in a lifetime of observing. 

Since the Moon and planets are all brightly lit by the Sun, a large light-gathering capacity is not as important as high magnification within the solar system. The relatively small aperture of a refractor is therefore often an advantage for this kind of observing, as is the high magnification capability of its long focal length, as there is less glare from brightly lit planetary surfaces to wash out faint detail. 

For purely visual lunar, planetary, binary and star cluster observing, an altazimuth refractor with slow motion controls may be perfectly adequate. If a family shares the telescope, however, an equatorial mount with slow motion controls or a motor drive will keep objects centered in the field of view so all can share the same view. If you plan on doing a lot of daytime terrestrial observing, the altazimuth refractor is a good scope with which to do it.