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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. 

Содержание 21182

Страница 1: ... 21182 INSTRUCTION MANUAL ...

Страница 2: ...eat build up can damage the telescope and any accessories attached to it Never use an eyepiece solar filter or a Herschel wedge Internal heat build up inside the telescope can cause these devices to crack or break allowing unfiltered sunlight to pass through to the eye Do not leave the telescope unsupervised either when children are present or adults unfamiliar with the correct operating procedure...

Страница 3: ...to secure the legs being careful not to over tighten 3 Stand the tripod upright and pull the tripod legs apart until the center brace snaps into place 4 Place the accessory tray on top of the center brace line up the keyed hole in the center Rotate the tray until the tabs at the three points of the tray snap into the holders on each arm of the tripod s center brace 2 11 1 12 4 7 8 10 1 Telescope T...

Страница 4: ...erence by using the azimuth tension knob on top of the mount Turn the knob clockwise to increase the tension and counterclockwise to loosen it THE TELESCOPE TUBE To attach the telescope tube to your tripod and mount 1 Move the mount so that the telescope mounting platform is parallel to the ground Lock the altitude clutch to prevent it from moving 2 Locate the dovetail bar mounted on the bottom of...

Страница 5: ...e the eyepiece in place 4 To see the sharpest image possible focus by looking through the eyepiece and slowly turning the focusing knobs until the image comes into sharp focus Your telescope comes with two eyepieces The 20mm which will give low magnification with a moderately wide field of view The 10mm will give you higher magnification but a narrower field of view Additional eyepieces can be pur...

Страница 6: ...e object you chose lies in the center of the view If the image is blurry gently turn the focus knobs until it comes into sharp focus LOOK THROUGH FINDERSCOPE Once the object is centered in your 25 mm eyepiece look through the finderscope and locate the red dot 3 ADJUST THE FINDERSCOPE Without moving the telescope use the two adjustment knobs to move the finder around until the red dot appears over...

Страница 7: ... clamp to the eyepiece clamp Slide the phone clamp up and down and rotate it left and right until your camera is looking down through the eyepiece of the telescope Tighten the knob on the bottom of the adapter to secure it in place Use the telescope s focuser to adjust focus of your camera Snap the image using your app Open the eyepiece clamp and place it around the body of the eyepiece Tighten th...

Страница 8: ...Press the button on the remote to trigger the shutter on your phone If your camera is in video mode you can press the button once to start recording and again to stop the recording 4 5 To insert or replace the battery place your thumb in the center of the back cover pressing inward and sliding downward remove the battery door The CR2032 battery should be inserted with the positive side facing upwa...

Страница 9: ...he Moon loosen the set screws on the focuser and remove the 20mm eyepiece Replace it with your 10mm eyepiece and tighten the set screws to secure it in place The 10mm eyepiece will give you significantly more magnification making the Moon appear much larger Note You may need to adjust the focus knobs when you change eyepieces to make sure you are getting the sharpest image possible Move the telesc...

Страница 10: ... 20mm Focal length of Telescope Magnification _________________________ Focal length of Eyepiece FIELD OF VIEW Determining the field of view is important if you want to get an idea of the angular size of the object you are observing To calculate the actual field of view divide the apparent field of the eyepiece supplied by the eyepiece manufacturer by the magnification it gives you in the scope yo...

Страница 11: ...bjects in the eyepiece In photographs of nebulae and galaxies you will see vivid reds and blues These colors are not visible when you look through the eyepiece The colorful images were very long exposure images taken over 15 60 minutes or more where your eye only records data on an instant by instant basis Digital sensors are much more sensitive to reds and blues than the human eye is which is mos...

Страница 12: ...t 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 th...

Страница 13: ... standard flashlight will causes your eye s irises to close down and it can take up to a half hour for your eyes to return to full dark adaptation Red lights do not have the same effect We recommend any red LED flashlight that has adjustable brightness output because even red light if excessively bright can affect your night vision These are available through most telescope retailers but can also ...

Страница 14: ...ticles 2 Use a photographer s squeeze bulb to blow away any loose debris You can also use a can of compressed air such as those sold for cleaning computer keyboards but you need to be careful Avoid using cans that are almost empty and be sure to hold the air can vertically Failure to do this can result in the can spitting propellant out onto the optics Hold the optical surface at an angle to the s...

Страница 15: ...stron com pages technical support or call 1 800 421 9649 NOTE This warranty is valid to U S A and Canadian customers who have purchased this product from an authorized Celestron dealer in the U S A or Canada Warranty outside the U S A and Canada is valid only to customers who purchased from a Celestron s International Distributor or Authorized Celestron Dealer in the specific country Please contac...

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