© 1999 by teh boon king. presented by... teh boon king
TRANSCRIPT
© 1999 by Teh Boon King.
Presented by...
Teh Boon King
Introduction
What is a telescope?
A telescope is an instrument which gathers light and amplifies it.
Types of telescopes
Refractor Reflector
Mountings
A telescope’s tube is just half of a complete telescope system. The other part of it is the mounting.
The mounting is the support which the telescope rests on in order for it to point to and track objects.
Types of Mounting
Alt-azimuth mount
Has 2 axis, up-down and side-to-side. Most basic mounts are alt-azimuth, e.g.
camera tripods, Dobsonian mounting. Has to move both axis in order to track a
celestial object.
Types of Mounting
Alt-azimuth mount
Basic alt-azimuth mount Dobsonian mount
Types of Mounting
Equatorial mount
Has 3 axis, where one is parallel to Earth''s rotational axis.
Able to track celestial objects by just moving on one axis.
This axis compensates for Earth’s rotation.
Types of Mounting
Equatorial mount
How to use a telescope
Familiarise yourself with the knobs, focus, locks, slow-motion controls, etc. of the telescope in daytime.
Dark adapt your eyes before observing. Use red flashlight to read charts, etc.
How to use a telescope
Equatorial mount Align the polar axis with the celestial pole
at your location. Proceed to next step.
Alt-azimuth mount Proceed to next step.
How to use a telescope
Identify your target object Locate the object in a star atlas. Find its position relative to the star field.
Look for recognisable patterns in the field.
How to use a telescope
Find the target object Use finder scope to locate the object within the star field
and centre it. Lock both axis of mount (if applicable). Use a low power eyepiece, focus and centre the object in
the telescope.
How to use a telescope
Start to observe! Use different eyepieces or barlow lens to achieve different
magnifications. Magnification = focal length of telescope
focal length of eyepiece Use colour filters for better contrast in observing planets.
Accessories
Eyepieces
Barlow lens
Finderscope
How to use a telescope
Tracking the objectEquatorial mount If motorised mount, just engage the motor and the telescope
will automatically track the object. If manual mount, use the slow-motion controls to move the
mount in the right ascension axis to track the object.
How to use a telescope
Tracking the objectAlt-azimuth mount Use the slow-motion controls to move the mount
in both up-down and left-right axis to track the object while looking at it through the eyepiece.
Observation Tips
TIPS
Be patient. If image looks fuzzy, wait until the sky calms down.
Practise. Observe as often as you can. At first you might not notice subtle details on some difficult targets, but as you go along, it will become easier.
Thank you for your attention. I wish you have a pleasant time using the
telescope to discover the beauty of astronomy.
BKTEH
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