Cannot See Anything Finderscope Crosshairs

Why can’t I see anything in my telescope when I have the Moon centered in the crosshairs of my finderscope?

For anyone with a telescope, a finderscope is a really important tool. Basically, a finderscope is a mini telescope that you fix on your main telescope’s back.

To be precise, a finderscope is attached near the rear of your main telescope. You can find it just above the eyepiece holder of your main telescope.

The purpose of a finderscope is simple but very useful. Actually, it helps aim the main telescope towards objects of interest. This allows you to view things in a much more efficient way.

A finderscope shows more of the sky as compared to seeing it through the telescope. It achieves this by using a wide field of view and low magnification.

With this wider field of view, you can “find” objects of interest very easily. This is particularly useful for later studying them at a higher magnification with the telescope.

Sometimes, having the moon centered in the crosshairs of your finderscope doesn’t show anything. This is a small, common problem for telescope users. Here’s our step by step solution.

Why you can’t see anything in your telescope and how you can fix this

For a finderscope to work, you need to align it with your telescope. If you can’t find objects in your telescope, your finderscope isn’t aligned with your telescope.

It is very easy to align a finderscope with a telescope. You, first, need to take your telescope outside. Make sure you do this during the daytime when there is plenty of light.

Then, find an object that is a good distance away from you. The distance should be at least quarter or half of a mile. Alternatively, you can choose something a few yards away.

What object you choose matters a lot as well. You need to pick an object that is uncomplicated and does not move around at all.

For example, a chimney, light post, aerial, telephone pole, or license plate are good options. A tree or even the moon are not good options.

This is because they are constantly moving. Also, it is hard to focus on a tree on one specific point. Therefore, you must select an appropriate object.

Now, in your telescope’s focuser, put your eyepiece that has the lowest magnification or power. It is simple to find this eyepiece. It is the one with the highest focal length in millimeters.

You focal length should, at least, be 20 mm. This is an ideal choice that gives you a considerably wide field of view. Now, look into the eyepiece of your main telescope.

You must aim your main telescope in the general direction of your chosen object. Try to get your view as sharp and clear as possible. This is an easy, recurring task for telescope users.

You can do this by focusing your main telescope. After that, get the object as close to the center of your view as possible. There’s a chance that you won’t be able to achieve this.

Telescopes aren’t designed to show nearby objects. So not can’t getting your object sharp in your telescope means that it’s too close. In this case, you’d need an object that’s further away.

There’s a chance that you’d see a mirror and upside down image of your object. This doesn’t matter if your chosen object’s image is sharp and at the center.

If you have got your object’s image sharp, lock off telescope so it can’t move. Now, look at your object through your finderscope.

You will notice that the crosshairs are probably not centered precisely on the object. To center it, you’ll have to use the adjuster screws on your finderscope’s sides.

Turn the screws to fix the finderscope’s direction. If the crosshairs are centered on the object, the finderscope alignment is complete.

Confirm your alignment

It is good if you double-check your alignment, which is a quick and simple task. For this, you need to use your finderscope to choose another, different object.

After this, look through your telescope’s eyepiece. Now, see if the object is centered on the view or not. If it is, your alignment is correct and confirmed.

Now, if you center anything, like the moon, on the finderscope’s crosshairs, it’ll appear clearly. Unless it gets bumped, your finderscope will remain aligned.

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