How To Clean A Telescope Lens: Our Simple Guide To Make It Shine

If you've grabbed yourself one of the best telescopes out there, then it's well worth knowing how to clean a telescope lens effectively.

Every stargazer has experienced a moment when their telescope lens begins to dirt up, and it’s a big deal. It’s not just a minor inconvenience; dirt on lenses or mirrors scatters light, consequently reducing the overall image quality.

So, to get a good, sharp view through your telescope, it is essential that your optics are as clean as possible. In this article, we will discuss the best way to clean a telescope lens. Let's dive in!

How to Clean a Telescope Lens?

Whether you're using a refractor or reflector telescope, a dirty lens will not allow the telescope to perform its best. It will reduce the quality of the output of your equipment. Therefore, it is necessary to clean your telescope lens. However, it is not recommended to clean the lens or mirror of your scope if it only has a few specks of dust.

In the case of lenses, too much cleaning is worse than too little. Because overly frequent cleaning can damage and prematurely age the special coatings on mirrors and lenses, thereby degrading their performance. So, it is recommended to clean your telescope only when it's absolutely necessary. Clean it once a year and it will be fine.

Read More: How to clean binocular lenses properly

Before we explain the process, you will need the following cleaning tools to clean your telescope safely and effectively: a rocket blower, a soft lens cleaning brush, a cleaning solution (isopropyl alcohol or methanol), and a clean microfibre cloth.

These cleaning kits are regularly available, (this one has some pretty good reviews in fact), and gives you everything you need to make your telescope look brand new.

click to enlarge
A squeaky clean telescope lens

Assuming that you already have these tools in your custody, let's dive into the main part. Here is how to clean your telescope lens:

  • The first step is to blow off all the dust and debris using your rocket blower.
  • Then gently flick off the last bits of dust using the soft brush.
  • Now take clean microfibre cloth and spray some cleaning solution onto it. Next, gently wipe the entire surface of the lens with the microfibre cloth to get rid off persistent dirt or smudges. DO NOT scrub, just wipe. 
  • Then, immediately dry the lens by wiping it with a dry microfibre cloth.

That's it! Your telescope is now ready for another session of stargazing. Take it out, set it up and enjoy the wonders of the Universe!

Read More:Telescopes vs Binoculars - Which Is Better For Stargazing?

Some Points to Remember

Cleaning telescope lenses is not to be taken lightly. Here are some cautionary notes:

  • It is not advisable to disassemble your telescope to clean it, as putting it back together is difficult and likely to go wrong. However, if you are confident enough, you can do it yourself.
  • It is not recommended to clean or touch the internal mirrors, because if it is not done rightly, it will damage the mirror coating. Let the professionals do it. 
  • DO NOT use abrasive cleaners, because it will scratch the mirror coating.
  • Always put on the lens cap whenever the telescope is not in use.
  • The instrument should be kept facing down. That way dust won’t settle on them in storage.
  • NEVER touch the surface of a lens or mirror.

Keep these pointers in mind, and you will be able to clean your telescope lens with confidence. Hope it helps!

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