Opticstar AR80S GOLD GUIDE-SCOPE, Руководство пользователя

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© Opticstar Ltd 2011
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Deep sky observation greatly depends on the prevailing sky conditions. City lights,
low sky transparency and the presence of the Moon will greatly affect what you can
see through the telescope. From a dark site and under favourable conditions you will
be able to see several deep sky objects including star-clusters, galaxies, nebulae and
comets. Such objects with the exception of stars will appear as feint clouds of matter
in monochrome, human eyes are not able to pickup colour. Cameras on the other
hand can reveal colour and considerable amounts of detail.
Good deep sky objects to look for with a small telescope include the Orion Nebula,
the Trifid nebula, the Ring nebula, the Andromeda Galaxy and a number of star-
clusters among various other objects.
Observation Skills
In general it is easier to locate a target with a low power eyepiece i.e. 25mm. Once
the target has been located centre it in the field of view before replacing the 25mm
eyepiece with a high power one, i.e. 4mm (x100).
There are many factors that will affect the quality of the image through the eyepiece,
such factors include sky quality in terms of the level or light pollution, sky
transparency and the presence of the Moon if you are observing deep sky objects
like galaxies and nebulae. If you use an equatorial mount make certain that the
telescope has been balanced and that all screws are reasonably tight.
You will always be limited by the type, size and the optics of your telescope in what
you can see. However there are other important factors to consider that can
substantially improve the experience. Let the optics to cool down for best results,
this varies depending on the size and type of the telescope but typically an 80mm
refractor like the AR80S will need around 15 minutes to cool down.
Please keep in mind that targets near the horizon will not look as sharp, targets near
the zenith will look substantially sharper. Avoid setting your telescope on concrete;
wood and grass are better as they do not release heat. Your line of sight should
ideally not pass just over a warm house, the rising heat will substantially affect the
quality of the image.
The fast focal ratio of the AR80S scope makes ideal for deep sky viewing and
imaging or for use as guide scope. When conditions are not favourable the
maximum useful magnification for most scopes will be around 25-35 times per inch
of aperture. Otherwise expect higher practical magnifications per inch of aperture
under favourable conditions with good quality eyepieces.
Dew shields are useful as they cut stray light entering the telescope, they also protect
objective lenses from dew building up on the optics. The AR80S comes with a
retractable dew-shield which should always be used.