How to fix my finderscope on my telescope?
TheOriginalSara asked:
Whatever I see through the finderscope is not what the telescope sees
It seems to be some distance off because after searching for a while through the eyepiece I see the object not far off from where the finderscope thought it was, but it takes a very long time and is very inconvenient.
It’s a reflector telescope. If anyone knows how to fix this please explain in simple language
thanks!
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Whatever I see through the finderscope is not what the telescope sees
It seems to be some distance off because after searching for a while through the eyepiece I see the object not far off from where the finderscope thought it was, but it takes a very long time and is very inconvenient.It’s a reflector telescope. If anyone knows how to fix this please explain in simple language
thanks!
March 8th, 2010 at 4:42 am
It’s something you really need to do in daylight. Find a distant object on the horizon (at least 100 yards away, preferably 1000+) in the main telescope and adjust the finder adjustment screws until it is pointing in the same direction. There’s no real secret to it but it does become easier in practice.
The only thing I’ll add is that if your finder has two sets of adjustment screws (front and rear) be aware that each set has the opposite sense for the same adjustment - if you want to adjust the scope in one direction you can move the rear screw in one direction or the corresponding front screw in the _opposite_ direction. Andrew S
March 10th, 2010 at 7:33 am
It all depends on what kind of telescope and what kind of finderscope.
On some finderscopes, the tube is held up by a number of screws. It is possible (but not always easy) to realign the finderscope by tightening one screw and loosening another one (simultaneously).
Also, the main telescope may need to be align every once in a while (the main mirror has to be perpendicular to the light path in most models). In reflectors, this is often does with three screws that push on the back of the mirror, while three other screws hold up the mirror cell into the tube (you have to play with the correct ones).
And, in many telescopes, these screws are located just so that you cannot reach the eyepiece while turning the screws. You need an elaborate mirror system to see what you are doing, or you need a friend who can turn the screws while you look.
However, if you are not experienced in that kind of stuff, don’t play with the main mirror (at least, not yet). Try to see if there is a way to realign the finderscope.
With everything turned off (and during the day), point the telescope at some distant, fixed land object (NEVER point at the Sun — Never) like a church spire, a road sign, a light post…
With the main tube pointing at that object, try adjusting the finderscope until the object is centred in it. Raymond
March 10th, 2010 at 9:04 pm
To align the finder with the main, use low power eye piece and focus on a distant object with the main scoipe.This will be easy if you use a low power eye piece.Then look through the finder, adjust the screws and bring the cross hair to the center of finder. Chandramohan P.R
March 13th, 2010 at 9:20 am
And here’s some pictures that illustrate the process - Nyx
March 16th, 2010 at 4:13 pm
During the day, center your telescope on an object that is easily identified (a mountain top, a building top, or something far away). Then, without moving your telescope, adjust your finder scope to center on the object. That’s all. You are now perfectly coordinated! threemilepingree