January 6, 2017

12 Do's and Don'ts for Maintaining Your Lenses

Lens cleaning
A lens maintenance expert of over 30 years shares his top tips for protecting your glass.

[Editor’s Note: No Film School asked Matthew Duclos of Duclos Lenses to share his lens maintenance expertise.]

There’s a ton of information and advice on proper cinematography techniques from self-professed experts floating around the internet. After having operated for 30 years, we’d like to set the record straight on a few topics specific to lens care by sharing what we at Duclos Lenses consider standard policy for our staff of experienced technicians. 

Here are a few simple dos and don’ts to keep in mind the next time you sit down to perform a bit of maintenance on your favorite lens. Following these simple rules can save you hundreds or even thousands of dollars on a costly element replacement.

DO's

1. Do only what is absolutely necessary

This is possibly our most important tip. Don’t undertake more than your skill level can handle and over-do it. We find that not observing this rule is the number one cause of lens element surface damage.

2. Work in a clean, temperate environment

Attempting to clean a lens element in a dusty, windy environment can not only be frustrating, but it can also leave you worse off than when you started.

compressed air
Using compressed air on a FUJINON PL 14-35mm Cabrio zoom lens

3. Blow off particles before wiping an element

Compressed air can be your best friend. Removing dust, dirt, and debris with a quick blast of clean, compressed air can remove large, harmful particles quickly and simply.

4. Work from the center out to the edge when using wipes

This is primarily to avoid picking up harmful particles that are commonly found between the front element and it’s outside housing. Working from the center out minimizes this risk.

5. Use a cleaning solution to remove contaminants

The best way to clean stains or contaminants off your lens is with a liquid cleaning solution applied directly to a wipe, but never sprayed on the lens element itself.

6. Use a soft bristle brush to remove sand, dirt, and debris from the lens body.

Never to be used on the glass itself, a brush can be a very effective tool for removing large contaminants from the intricate nooks and crannies of a lens body.

Soft bristle brush
Using a soft bristle brush on the body of a FUJINON PL 14-35mm Cabrio zoom lens

The DOs are important. But the DON’Ts are even more important. As we mentioned in the first DO rule, only do what’s absolutely necessary. The least amount of contact you have with your lens, the better off you’ll be. Prevention is the best method for maintaining a perfect, clean lens.

DON’Ts

1. Don’t use any reusable cloths or wipes on a lens element

Microfiber cloths can be very useful for cleaning the anodized exterior of a lens, but should never be used on a glass element. Microfibers are designed to trap particles from the surface they’re cleaning. After a few uses, a microfiber effectively becomes sandpaper for your lens.

2. Never reuse a lens tissue of any kind

Once you’ve wiped your lens element and lifted the tissue away, it’s trash. Never lift a tissue away and then reuse it. Even high-end, lint-free wipes should not be used more than once.

3. Don’t spray cleaning solution directly onto your lens

Lens cleaning solutions come in all sorts of sizes, shapes, and styles but they have one thing in common—they shouldn’t be sprayed onto your lens. Spraying directly onto the lens can cause the liquid to penetrate the housing and build-up condensation inside the lens housing.

lens cloth
Never spray directly onto your lens.

4. Don’t use brushes on lens elements

Lens brushes can be useful for the lens body, but using them on the element itself can just spread oils and debris and potentially cause damage.

5. If you’re using canned air, don’t shake or tip the can while spraying.

It’s best to spray the can upright, away from your lens for a second to clear any propellant out of the nozzle. Spraying propellant onto your lens element can potentially damage it.

6. When in doubt, bring your lens to a professional

A good service shop should offer to do a basic cleaning at no charge. When it comes to simply cleaning the front and rear elements, a skilled, experienced service shop should be able to take care of most common cleaning tasks in a matter of minutes. 

There are dozens of other tips that we could offer but these general rules should get you through most situations. As in most situations, there’s an exception to every rule, so please don’t consider this quick guide absolute. As long as you use common sense and don’t hesitate to get advice from a professional lens shop when necessary, your lenses should be in good shape. Any questions specific to lenses, please fire away in the comments section below.      

Matthew Duclos is the Chief Operating Officer and Project Manager of Duclos Lenses which specializes in the repair and maintenance of professional motion picture lenses including Fujinon Angenieux, Arri, Canon, Cooke, Rokinon, Schneider, Voigtlander, Zeiss, Century, Hawk, Red, and many more. 

Your Comment

7 Comments

Not part of cleaning but do:

- If you're not shooting something critical or something that requires taking it out, always use a UV filter on your lens. (It actually saves asses big time and distortion is close to zero).

- ALWAYS store your lenses with BOTH caps. Minimise the dust build-up.
It's amazing how careless some people can be.

... there are a lot more... but well...

Good article ;)

January 6, 2017 at 1:13PM

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Ismael Abufon
Photographer
1

So I should take the brillo pad out of my AC kit?

January 6, 2017 at 3:01PM

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Filmbaker
Writer/Director
348

Any reader comments about the use of carbon particle lens pens? I've used one a little on a lens I wasn't particularly attached to and it seemed okay. I keep one in my bag to be used only on a UV filter.

January 6, 2017 at 3:32PM

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Periodically vacuum out your lens bag to remove dirt and loose fibers (remove camera and lens first!) and remember to keep the the inside of your lens caps very clean when not covering your lens. Any fluids applied to a lens can migrate into areas with lubricants and wick dust and dirt from the surface of the lens into the internals. Also these alcohol and Freon based cleaners while safe for coated glass optics, can cause lubricants and grease to migrate to areas where they can cause trouble so keep the liquids used to the absolute minimum, both in number of applications and amount of fluid applied to the cleaning tissues.

In high moisture environments, you can keep a handful of the white Tyvek wrapped silica gel moisture absorbers in your camera bag. The better ones are re-usable and can be re-activated in your oven after they saturate with water vapor. Make sure they do not leak the clear white beads or any powder into the bag as that would require professional cleaning immediately to remove the abrasive silica gel. Otherwise they are a safe way to keep the moisture down when the equipment is stowed away between shoots.

Otter and Pelican hard cases work well for cine storage, but always inspect your foam for foam rot if you use it to protect lens and bodies from travel and shipping vibration and damage. Little particles of foam can get stuck inside your lens and camera body and it is hard to see it when the foam is black on a black lens or body.

Paying for professional cleaning and inspection after dusty shoots is always money well spent unless lens tech is your hobby. A good lens tech will have a laminar flow hood with a rated HEPA filter in good condition to work in, so ask about their cleanroom environment investment. Laminar flow hoods provide a continuous clean curtain of sub micron filtered air that exhausts onto the operator so that the lens and camera body can be cleaned without introducing more dirt into those tight tolerance components. That way they can disassemble, clean and re-assemble your optics without introducing more particulate contamination into the works during this invasive process. Yeah they cost at at least a couple of grand to buy but then again so do cine lens.

January 6, 2017 at 5:06PM, Edited January 6, 5:06PM

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Great insight David! Thanks!

January 11, 2017 at 9:19AM

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Chris Niswonger
Filmmaker
153

S

January 6, 2017 at 6:27PM

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I would argue that you should not use canned air on lens elements regularly. In my experience it eventually leaves build up of the propellant on the lens, which requires deep cleaning from time to time. I prefer a manual blower.

May 29, 2017 at 12:03PM

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