Selecting An Observing Site; Choosing The Best Time To Observe; Cooling The Telescope; Adapting Your Eyes - Celestron LCM Serie Manual De Instrucciones

SELECTING AN OBSERVING SITE

If you are going to be observing deep-sky objects, such as galaxies and nebulae, you should consider traveling to a dark sky site that is
reasonably accessible It should be away from city lights, a relatively unobstructed view of the horizon, and upwind of any major source
of air pollution Always choose as high an elevation as possible as this can lower the effects of atmospheric instability and can ensure
that you are above any ground fog While it can be desirable to take your telescope to a dark sky site, it is not always necessary If
you plan to view the planets, the Moon or even some of the brighter deep-sky objects, you can do this from any location, such as your
own backyard Try to setup the scope in a location that is out of the direct path of streetlights or house lights to help protect your night
vision Try to avoid observing anything that lies within 5 to 10 degrees over the roof of a building Rooftops absorb heat during the
day and radiate this heat out at night This can cause a layer of turbulent air directly over the building that can degrade your image It
is best if you set your telescope up directly on a dirt or grassy surface Setting up on any raised platform such as a wooden deck or a
hard surface like concrete or a sidewalk should be avoided as they transmit vibrations easily that can be transferred to the telescope
Observing through a window is not recommended because the window glass will distort images considerably And an open window can
be even worse, because warmer indoor air will escape out the window, causing turbulence which also affects images Astronomy is an
outdoor activity

CHOOSING THE BEST TIME TO OBSERVE

Try not to view immediately after sunset After the sun goes down, the Earth is still cooling, causing air turbulence As the night goes on, not
only will seeing improve, but air pollution and ground lights will often diminish Some of the best observing time is often in the early morning
hours before dawn Objects are best observed as they cross the meridian, the imaginary line that runs from north to south through a point
directly over your head This is the point at which objects reach their highest points in the sky and your telescope is looking through the least
amount of atmosphere possible Objects that are rising or setting near the horizon will suffer more atmospheric turbulence since you are
looking through a much longer column of air It is not always necessary to have cloud-free skies if you are looking at planets or the Moon
Often broken cloud conditions provide excellent seeing

COOLING THE TELESCOPE

Telescopes require at least 10 minutes to cool down to outside air temperature This may take longer if there is a big difference between the
temperature of the telescope and the outside air This minimizes heat wave distortion inside the telescope tube (tube currents)

ADAPTING YOUR EYES

If you are planning to observe deep sky objects at a dark sky site, it is best if you allow your eyes to fully adapt to the dark by avoiding
exposure to white light sources such as flashlights, car headlights, streetlights, etc It will take your pupils about 30 minutes to expand to
their maximum diameter and build up the levels of optical pigments to help your eyes see the faint light from a distant target If you need light
to help setup your telescope in the dark, try using a red LED flashlight at as low a brightness setting as possible and avoid looking straight
at the light source This will give you the best chance of capturing those faint deep sky objects
When observing, it is important to observe with both eyes open This avoids eye fatigue at the eyepiece If you find this too distracting, cover
the unused eye with your hand or an eye patch The center of your eye works well in bright daylight, but is the least sensitive part of the eye
when trying to see subtle detail at low light levels When looking in the eyepiece for a faint target, don't look directly at it Instead look toward
the edge of the field of view and the object will appear brighter
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