How To Clean Telescope Lenses

In this article I will walk you through the 5 simple steps needed to effectively clean your telescope lenses. While the task may seem daunting at first, if you following these 5 simple steps you’ll improve your viewing experience immensely.

Using Protective Cases and Lens Covers
Using Compressed Air
Using a Soft Brush
Using a Microfiber Cloth
Using Lens Cleaning Fluid

As a general rule with any lens, or mirror cleaning for that matter, less is usually more! Try to resist the urge to clean your telescope lenses for as long as possible. Resist for at least as long as it is just unbearable and is diminishing your evening viewing experience.

Throughout this article we will review each of these steps in explicit detail so you know how to implement each technique properly. Using the wrong materials or techniques for cleaning your telescope lenses can result in irreparable damage.

I have to assume that if you’re searching this topic on the Internet then, like I was, you’re a little worried about how or if you should clean your telescope lenses. Or if you are brave enough to do it, asking yourself, am I doing it right?

Truth is cleaning your telescope lenses is not “rocket science”…no pun intended! In fact, it’s pretty straight forward if you take the necessary precautions and have the right tools to do the job.

Near the end of this article is a YouTube video by Orion Telescopes that does a decent job that covers off everything we are going to discuss here. I recommend you give it a watch after reading this article.

I should put a disclaimer out there right now regarding your telescope mirrors…DON’T DO IT! This article relates only to the lenses in your telescope and not the mirrors. In fact, I recommend having the mirrors cleaned by a professional.

Given the proper amount of time and care, your telescope lenses will give you years of viewing pleasure with proper maintenance and cleaning. The good news is you really don’t have to spend a lot of money to do it either. Typically, a good lens cleaning kit, like this one from Orion, is all you’re going to need!

A few notes before we get started. Your telescope lenses many not require all of the steps we are going to cover off here. In fact, if after Step #1 you are satisfied with you results…then stop! However, if Step #1 doesn’t get you the result you’re looking for, then proceed to Step #2 and so on…

Step #1 – Use Protective Cases and Covers

I know you’re probably thinking…what does this have to do with cleaning your telescope lenses? Well it doesn’t, however, I firmly believe that it is a sound strategy to ensure that the frequency by which you need to clean your telescope lenses is dramatically reduced.

Invest In Dust Caps, Protective Cases and Dew Shields…

Amazon has a wealth of accessories when it comes to these types of items. Dust caps are probably the most inexpensive way to keep your lenses clean and dust free. If you’ve lost or misplaced your eyepiece covers then check out these Dust Caps for 1.25″ Telescope Eyepieces.

I also recommend that if you don’t have a good eyepiece carrying case then to invest in one straight away. Your collection of eyepieces and lenses will quickly become the most valuable items of your whole telescope ensemble, so show them the love they deserve and protect your investment.

Again Amazon has many cases to choose from, but I recommend the Orion Deluxe Large Accessory Case for its rugged design and portability.

The other item I recommend investing in is a Dew Shield. A dew shield is an essential accessory that protects your optical tube from excess moisture forming condensation on the corrector lens. A lens shade also helps block out stray light outside the path of the telescope for better viewing and astro-imaging.

On clear nights, dew is often a real problem. After only a few hours, the optics start fogging, making observations or photography impossible. A good dew shield reduces the risk of fogging and extends the observing time. Dew can be a problem at almost any time of the year. Especially when it’s a little cooler, tiny droplets condense out from the water vapour in the air and fog-up the optics of your telescope

Step #2 – Using Compressed Air

Like I said in Step #1, the best practice for keeping your telescope lenses in pristine, clear and clean condition is to ensure you invest in good protective covers, cases and accessories. Unfortunately, after frequent…or even infrequent use, your lenses are bound to require some amount of cleaning at some point.

Therefore, the next option you should be considering is one where contact to the lenses is avoided. That’s right, the less you have to physically touch the telescope lenses the better.

WARNING…DO NOT USE YOUR BREATH!!!

Resist the urge to blow dust particles off with your breath! Your breathe contains tiny water droplets (otherwise known as spit) and this will not help clean your telescope lenses!

Instead, get yourself some compressed air, or any popular lens cleaning kit such as the one from Orion I mentioned above.

I’m also a big fan of the Tycka Professional Lens Cleaning Kit that has an air-bulb (blower) included.

While I’m not a huge advocate of using compressed air to do the cleaning. Some friends of mine use it all the time.

For me the built in air-bulb included in the aforementioned cleaning kits is more than adequate, but if you want a little more “blowing power” then you could certainly go the compressed air route by purchasing a 4-Pack of Compressed Air from Amazon or your local electronics retailer.

Step #3 – Using a Soft Brush

It is no mistake that we are going in this order of steps to clean your telescope lenses. Remember, the less we physically touch the lenses the better. However, there will be times when an air-blow won’t be enough. That said, if you’re satisfied with the job the air-bulb or compressed air did in Step #2, stop now!

This is where I recommend using a soft brush designed to clean lenses…

I know we are talking telescopes here, however, any cleaning kit designed for cleaning optics and lenses will do the trick.

Like I mentioned above, you won’t be disappointed with the Tycka Professional Lens Cleaning Kit. While it says its for cleaning a DSLR camera, it will work just as well as any kit advertising itself for telescopes.

The key to using a brush is to make sure that it is extremely soft and designed for lens cleaning applications.

I also recommend that when not using the brush that it be stored in a bag or a provided carrying case so that it doesn’t collect its own dust when not in use. Luckily any of the cleaning kits I’ve recommended here will provide it’s own travel case.

When using the brush be sure to do light, gentle flicks on the lens area from the center of the lens to the outside…that’s it! No real technical or special requirement needed!

Step #4 – Using A Microfiber Cloth

At this point, I’m hopeful that any accumulated dust or dirt on your lenses is effectively gone. If so, and like in previous steps…stop now!

Only continue with these steps if there is evidence of oils or fingerprints on your lenses and eyepieces…

Okay, so you have some nasty fingerprints on your lenses, or perhaps there is evidence of eye-lash oil residue…which is common!

The first step will be to take the microfiber cloth out that came with your cleaning kit and then gently rub the surface of your lens with it.

Do this dry as you don’t want to use lens cleaner just yet if not needed…

Again, less is more so if we can get the oil and scum off with just the dry microfiber cloth then it’s the proverbial, “Bob’s your uncle”! However if the scum and oil remain, our last course of action is lens cleaner.

Step #5 – Using Lens Cleaner

If you’ve gotten to this step then likely you are not satisfied with the results from the previous steps. That’s okay, while most of the time Steps #1 thru #4 will yield good results, there are instances when it’s just not enough.

Using the lens cleaner from one of the lens cleaning kits I recommended, apply a couple of small drops to the microfiber cloth on a clean area. What you don’t want to do is apply the lens cleaner directly onto the lens area. This can create other issues if the cleaner penetrates the lens along the edges.

Do Not Apply Lens Cleaner Directly To The Lens…

Once the lens cleaner is applied to the microfiber cloth, use a gentle circular motion to the lens to clean the glass. Once satisfied, use a dry part of the microfiber cloth to repeat the gentle circular motion in precisely the same direction as you applied the cleaner.

This should be sufficient to remove any excess cleaning fluid that may be left on the lens.

The key to cleaning your telescope lenses to take the time and care needed. Be firm, but also gentle at the same time.

That’s pretty much it! You’ve just learned the 5 simple steps on how to clean telescope lenses. As promised, here is the YouTube from Orion Telescope where they discuss, How To Clean Telescope Lenses!

How To Clean Telescope Lenses – What Have We Learned?

To recap the 5 simple steps to cleaning telescope lenses, I thought it would be useful to do a quick recap. While telescope lens cleaning is not a difficult task in itself to perform, it should not be taken lightly or performed haphazardly either!

Always use care when cleaning your telescope lenses and follow these simple rules and cautions:

Mirrors and lenses are not the same thing in a telescope. These steps to cleaning telescope lenses only apply to lenses and not to mirrors. Therefore, do not use these approaches when trying to clean the mirrors of a telescope. My advice – take the mirrors and/or your telescope to a professional who specializes in telescope cleaning.

Do not get overly concerned with cleaning your telescope lenses and eyepieces. LESS IS MORE when it comes to cleaning your telescope lenses. The truth is, things will need to get pretty “gummed” up and dirty to diminish your viewing experience at night. Take my advice, spend more time looking through your telescope lenses then worrying about how clean they are.

Do make regular use of the kit supplied air-bulb. A light “blow” is all that you’ll need before going out on your next stargazing adventure. Also, this type of routine maintenance will ensure that full-on lens cleaning will be kept to a minimum.

Don’t take your lenses out of your telescope or eyepiece to clean them. This is just going to damage your hardware and likely cause you to have to replace it. Just don’t, as it is not required anyway.

Depending on how often you use your telescope, I would keep full-on lens cleaning to no more than once per year. Unless there are obvious signs of contaminants, use one of the other methods first.

How To Clean Telescope Lenses – Additional Reading

Well I hope you’ve enjoyed this article, “How To Clean Telescope Lenses – 5 Simple Steps”, and have found it useful. If you did, consider checking out my other articles that are full of equally good tips and tricks for everything amateur astronomy and stargazing. You’ll find them here: