New telescope users are taken by surprise at the difficulty of just pointing the telescope in the right direction to see anything. The field of view is quite limited, especially if you are using a high power eyepiece. The higher the power of eyepiece on a telescope, the dimmer the image, the more difficult to aim it at any chosen object, and the more difficult to focus. When the scope is not focussed, even if there are stars in the field of view, they will only be faint blurs.
It is best when you are starting out with a telescope to try it with the least powerful eyepiece (the one with the highest number) to begin with, until you become more familiar with how it works. Do NOT use the Barlow lens if one came with the scope.
The finder scope is meant to help you get the main scope lined up on the object you want to view, but it won't be any use in pointing the telescope until you adjust it to precisely line up with the main scope. Telescope manuals recommend that you do this in daylight, by pointing the scope at an object on the horizon and adjusting the finder to match (never point a telescope toward the Sun!). Once you have a tree or mountain peak in the center of the main scope's image, you can then adjust the screws around the finder scope to get the crosshairs (or red dot) centered on the same object. It is very difficult to do this job in the dark, especially as objects in the sky are constantly on the move.
You will find that there is a very wide range of movement in the focus mechanism, because different eyepieces focus at different points, but the actual focus range for any eyepiece will be a small part of the overall range afforded by the focusing mount. It is much easier to familiarise yourself with this in daylight.
At this point you will learn that astronomical telescopes usually show an upside down image. There is a good reason for this- erecting the image needs more bits of glass in the light path, which reduces the amount of light and increases aberrations. Even if this is only slight, astronomers prefer to avoid it, and they don't really care which way up the Moon or Jupiter appear. It is possible to fit an erecting prism or eyepiece to most astronomical telescopes, and some of them come with one, but one wouldn't bother to do this with the small finder scope.
Once you have done the above, you can try the scope at night, on an easy to find bright object like the Moon. Looking at random stars will probably be disappointing, as they don't look different under magnification. You will have to find planets, star clusters or nebula to see anything interesting. You will also find the the object you are looking at swims out of the viewing field, and you must continually move the scope to follow it. This will be more pronounced at higher magnifications. Again, use the least powerful eyepiece. Small scopes are often advertised as having unrealistic powers (300, 500) which can never be practically achieved. You just get dim blurs.
There is an excellent website for beginner telescope users at THIS LINK
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New telescope users are taken by surprise at the difficulty of just pointing the telescope in the right direction to see anything. The field of view is quite limited, especially if you are using a high power eyepiece. The higher the power of eyepiece on a telescope, the dimmer the image, the more difficult to aim it at any chosen object, and the more difficult to focus. When the scope is not focussed, even if there are stars in the field of view, they will only be faint blurs.
It is best when you are starting out with a telescope to try it with the least powerful eyepiece (the one with the highest number) to begin with, until you become more familiar with how it works. Do NOT use the Barlow lens if one came with the scope.
The finder scope is meant to help you get the main scope lined up on the object you want to view, but it won't be any use in pointing the telescope until you adjust it to precisely line up with the main scope. Telescope manuals recommend that you do this in daylight, by pointing the scope at an object on the horizon and adjusting the finder to match (never point a telescope toward the Sun!). Once you have a tree or mountain peak in the center of the main scope's image, you can then adjust the screws around the finder scope to get the crosshairs (or red dot) centered on the same object. It is very difficult to do this job in the dark, especially as objects in the sky are constantly on the move.
You will find that there is a very wide range of movement in the focus mechanism, because different eyepieces focus at different points, but the actual focus range for any eyepiece will be a small part of the overall range afforded by the focusing mount. It is much easier to familiarise yourself with this in daylight.
At this point you will learn that astronomical telescopes usually show an upside down image. There is a good reason for this- erecting the image needs more bits of glass in the light path, which reduces the amount of light and increases aberrations. Even if this is only slight, astronomers prefer to avoid it, and they don't really care which way up the Moon or Jupiter appear. It is possible to fit an erecting prism or eyepiece to most astronomical telescopes, and some of them come with one, but one wouldn't bother to do this with the small finder scope.
Once you have done the above, you can try the scope at night, on an easy to find bright object like the Moon. Looking at random stars will probably be disappointing, as they don't look different under magnification. You will have to find planets, star clusters or nebula to see anything interesting. You will also find the the object you are looking at swims out of the viewing field, and you must continually move the scope to follow it. This will be more pronounced at higher magnifications. Again, use the least powerful eyepiece. Small scopes are often advertised as having unrealistic powers (300, 500) which can never be practically achieved. You just get dim blurs.
There is an excellent website for beginner telescope users at THIS LINK