How to adjust the finder scope - Vivitar Optics

Place a wide angle, that is longer focal length lens in the scope in daylight and focus it and centre on some distant object, a tree, blg, tower etc.

Then use the adjustment screws on the finder to centre it on this same object.

Change to your next higher power lens, that is shorter focal length, refocus and centre, and repeat with the finder adjustment.

Next wait for evening and a bright star or planet to appear and centre it in the finder first this time. It should be somewhere near centre in the lens also. Centre it properly in the lens and make a final adjustment on the finder.
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The "finder-scope" as they are called can be lined up by putting a low-power eyepiece in the scope, and moving the scope (on its mount) to view a distant object such as a streetlight. An EP which gives you about the same magnification as the finder-scope is a good choice. They are mostly about x8 power.


Centre the object in the eyepiece view and then adjust the finder-scope until the object is centred in that view as well.


Repeat this with a higher power EP, then move the scope onto a bright star, and use the highest magnification EP you have to finally do the last tiny adjustment to the finder-scope.

They must be lined up, and if you are using a higher power eyepiece, this must be more precise as your field of view is smaller.
There will be some type of adjustment on the finderscope, probably 3 thumbscrews around the holder tube.

Put in a low power eyepiece and point the scope at a local feature such as a streetlight or distant building. Get this centered in the eyepiece. Then adjust the finder only so the feature is centered in the finder as well.

Put in a higher power eyepiece and center the feature again in the telescope EP, and readjust the finder centering by itself, if needed.

Then choose a bright star and by moving the scope mount, place this in the center of the finder. Check if the star is properly centered in the EP as well and if not, move the scope mount until it is. Then finally adjust the finder centering by itself.

Unfortunately I can not get the manual for this. I do not think you need collimation at this time. You need to adjust the finder on the scope. Use the highest number eyepiece (lowest power) and point the scope towards a landmark during the day. Now look through the finder. Loosen the screws of the finder and move it until the finder LED is pointing towards the landmark. Tighten the screws.
Note: This telescope is more of a toy than a good telescope. Avoid scope that advertise max power in their name. This scope is unable to make 575x! Max power is 50x per inch of aperture on a very good night. 76mm=3in x 50 =150x max!

The finder scope must be aligned with the main tube. Get a bright star into the MAIN tube eyepiece. Then without moving the scope adjust the crosshairs in the small finder scope so they CROSS at the same star.

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.

Telescope manuals recommend that you align the finder scope in daylight, by pointing the main 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.

Your finder scope is NOT lined up with the main tube. Get a distant object like the top of a telephone pole into the eyepiece of the main telescope tube.

Without moving the scope adjust the crosshairs or the red dot onto the exact same spot. Now your finder scope is lined up with the main telescope tube.

You have NOT lined up the finder scope with the main tube. Point the scope at the moon or a bright star and get the moon or the star into the main tube's eyepiece.

Without moving the scope adjust the screws on the sides of the finder scope and center the crosshairs on the target. Now you can use the finder to line up the main tube.

The finder scope may not be aligned properly with the mn telescope. In the daytime, try setting the main scope on a distant object such as a steeple or chimney in the distance then align the finder scope to point to the same object. Then at night, look at the some bright star or planet and fine-tune the finder scope's adjustment screws so the images are aligned between the two scopes.

point the telescope at some thing during the day and adjust the finder scope and at night point at a star look through the eye piece and center the object in the eye piece then adjust the finder scope.