There is nothing more frustrating than getting the telescope out for a great observing session only to find that the telescope and finder-scope point to different areas of the sky, the stars appear as blurry spots, or the neighbor's security light is shining right into our eye, or see nothing at all. Follow this guide to setting up the telescope to make observing objects much more enjoyable.
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Step 1: Align the Finder Scope With the Eyepiece.
First, start by aligning the finder-scope. This should be performed during the day. Point the telescope at an object in the near distance (about a quarter mile). The top of a nearby streetlight, chimney or tree is a great choice. Once the top of the object is centered in the field of view, move over to the finder-scope and adjust the screws or dials so that the cross-hair or red dot points directly centered at the object in the actual telescope. A well-aligned finder-scope will make observations so much better and is worth spending time getting it right. This is because we now have the confidence that the object we are trying to see is going to be in the center of the field of view when looking down the eyepiece. Most importantly, Although this can be done anytime it is best done during the daytime.
Step 2: Orientate Yourself to the Image.
Different types of telescopes produce differently orientated images at the eyepiece. Some give an upside down image, others a mirror image and some do both. Spend some time looking through the telescope and work out what the telescope is doing. If looking at something familiar such as a stationary car in the distance and move the telescope around we can quickly work out what the telescope does to the image. For instance, look at the license plate to see if it is upside down and mirror image. Becoming orientated really helps when viewing an object like the moon or when searching for other objects.
Step 3: Locaton, Location, Location.
Next, think about where to place the telescope. Try to avoid hard surfaces, as these will cause the telescope to wobble when looking into it and when the telescope gets moved while looking for an object. Choose firm, stable but soft ground such as the lawn. Make sure to place the telescope in an area shielded from local light sources, like the street lights. Simply placing the telescope nearer to a fence, for example, to shield it from the neighbor's security light can make a big difference. We want to avoid these light sources entering the telescope. If this isn’t possible a dew shield over the aperture(big end) and a towel over our head will suffice. Lastly, make sure the telescope can be pointed at the area of the night sky to observe. There is nothing worse than having a house or tree obscuring the view of the planet that we were planning to observe that night.
Step 4: Give the Telescope Time to Acclimate to the Outdoor Conditions.
Finally, the air inside the telescope when taken outside is different from the air outdoors. This can lead to air currents or misting of the mirror. These can severely affect the view in the eyepiece. Make sure to place the telescope in its observing position at least thirty minutes before planning to start to observe. Different telescopes take different times to cool down but generally the larger the telescope's aperture the longer the cooldown will take. This is one of the reasons a very large aperture telescope isn't ideal for the beginner.
Step 5: Clear Skies.
That’s it really. Align the finder-scope, orientate with the telescope, find an ideal location and allow the telescope to acclimatize. Doing these simple steps will certainly make observing more successful and enjoyable.