How to focus a telescope?

Have you seen any pictures of people?  The figures are very clear, but the background is blurry.  This truth is the same as focusing, and the distance between the background and the camera is not the same, that is, the object distance is not the same.  This means that only one of the portrait and background images can be in focus, and the one that is not will be blurred, so focusing is what makes the subject you want to see clearly.  

Getting a clear image in the eyepiece is one of the most important things you can do when using a telescope.  Sometimes it’s hard to focus.  Each telescope has a different focus regulator, and the procedures even differ between different types of telescopes.  In this article, I’ll explain how to focus a telescope to help you get a sharp image.  

How to focus a telescope?  

Install eye cup: rubber visor can prevent stray light from escaping into the observation effect;  If you want to wear glasses, please remove or fold them back.  Adjust the rubber eyecup and fold the eyecup when wearing glasses.  No glasses, glasses up.  Rotate and slide the rubber eyecup, while wearing glasses, turn the eyecup clockwise to the fully retracted position.  Without glasses, turn the eyeglass counterclockwise to the fully elongated position.  Once the rubber eyecup is set up, you will have a clear and complete view of the telescope from the right spot, with or without glasses.  


Set your telescope to minimum Power: Focusing your telescope becomes easier if you set your eyepiece’s magnification to the minimum setting.  This is the highest available number in millimeters.  Also, to determine the magnification of a telescope, you must divide the focal length of the telescope by the focal length of its eyepiece.  

Assuming you have a focal length of 1,200mm and an eyepiece of 25mm, applying the above formula will result in 48 times magnification.  Keep in mind that the magnification of any telescope will be greater for a telescope with a smaller focal length eyepiece.  With this setting, you can more easily locate the objects you plan to center.  

Point the telescope’s viewfinder at the object: The main goal is to make sure the crosshairs are in the direction of the object you are looking at.  Since you’ve set the magnification and aligned the viewfinder, it’s easier to see the objects.  

Make sure the crosshair is centered on the target.  After the viewfinder is set in place, it or the telescope should not move or jerk in any other way, as this changes alignment.  

Set and align telescope eyepiece: After setting viewfinder, peer into telescope eyepiece and locate objects.  Move the telescope around freely, making sure it is centered.  If you are correctly aligned with the viewfinder, your eyepiece is likely to be close to the same setting.  The goal is for the viewfinder and telescope to focus together and on the same object.  If you are having trouble positioning with the eyepiece, try checking the viewfinder Settings and readjust as needed.  


Adjust pupil distance: the elbow of both hands, hand wall clamped to the chest to form a support point for stable observation;  Remember to keep your hands and arms open.  The two eyes are adjusted according to each person.  Only when the two images are combined into one can the stereoscopic effect of binoculars be played.  If the pupil distance is not properly adjusted, the image you see may be uncomfortable.  

Diopter adjustment: the elbows of both hands, hand wall clamped to the chest to form a support point for stable observation;  Use the middle finger of your right hand to push the center focus wheel until it is clear.  The right eyepiece of some binoculars can also be used for precise focusing, so users are required to rotate the central focusing wheel to make the left eye clear, and then close the left eye and use the right eye to compensate for more precise focusing, so that the right eye can be as clear as possible.  

Focus: From now on, when looking at objects at different distances, just adjust the focus ring to align the focal length, no need to adjust the focal length of the left and right eyepiece.  Never use binoculars to look at the sun or you will hurt your eyes.  

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