Lens cleaning

Approximate 7 minute read

A few years ago a TV show invited me to come by their set and take a look at their video projection system.  The producers complained that the projector looked dingy and they feared they would need to spend $10,000 to $100,000 to solve the problem, replacing the whole projector, or at a minimum the (expensive) lamp!

Confident their call to me was “well, he can’t make it any worse,” I inspected the projector.   One could see years of dust accumulated on the projector’s lens.  Some compressed air, lens cleaning fluid, lens tissue and fifteen minutes – I invited the producers to have a look at their projection screen.  Voila! A miracle had occurred! I “fixed” the projector and managed to do so during the crew’s lunch break.  The producers didn’t even lose a single minute of taping or incur any labor overtime!  I was a hero!

It’s not just projector lenses that get dirty! I am amazed by how many churches use their multi-camera set-up at most one or two days per week and do not “bag” their cameras on the days when not in use.  Capping a lens and bagging a camera, whether using a simple and inexpensive plastic trash bag or a professional overnight cover like those made by ShooterSlicker serve many purposes including discouraging theft and detering unsupervised minors from “playing cameraman” when not supervised (punishable by a commitment to be trained and serve on your AVL tech team, but that is a topic for another post)! Camera overnight bags also help keep dust, dirt and leaky ceiling drippings off your camera and the lens.  Cap your lens and bag your camera.

Regularly cleaning your camera lenses should be part of your AVL system’s scheduled maintenance routine. In the broadcast TV world, camera utilities (or in the film world, 1st and 2nd assistant cameramen/women) check lenses for dust or smudges before every taping. In general, lenses on these types of productions are cleaned at least once per day. If shooting outdoors, cleaning may be even more frequent. For the average church, checking lenses for dust or dirt should probably be done on a monthly, if not weekly basis .

There are more than one way to clean a lens and my way is by no means the only way.  But it works for me and I hope it will be helpful to you.

Putting together a lens cleaning kit

The first thing you should do is put together a kit of items you will need to properly care for your lenses.

Everbrite 3LED Rubber Flashlight

A flashlight.  A flashlight is used to shine into the lens making it easier for you to see where the dust or dirt is located on the lens.  I find smaller flashlights (that can fit under your chin, or in your mouth) work best so your hands can remain free.  You can probably make due with any flashlight you already have, but if you are buying new flashlight, Amazon has a two-pack of rubberized Everbrite LED flashlights for under $11 USD.  At $5.50 USD each, that’s not a bad deal.

Giottos AA1900 Rocket Air Blaster Large

A lens blower.  You will need a way to gently blow dust off the lens.  I recommend a lens blower bulb like the Giottos AA1900 Rocket Air Blaster which you can find online for about $11 USD.

Falcon FALDPS Plus Cleaning Spray

Now some people use Dust Off.  If you are going to use Dust Off, you may want to buy the can which has the swivel nozzle.  When blowing dust off of a lens it’s best to hold the lens upside down and blow air from underneath at a diagonal angle.  The can with the swivel nozzle is much more convenient to get the air coming from underneath at the correct angle. Please also note that some canned air products have oils or chemicals which can damage your lens.  If you opt for a cheaper canned air solution, check the ingredients.  Lastly, it’s important to know that many canned air products including Dust Off contains difluoroethane (DFE), which some people, usually young people “huff” to get high.  Knowing that, it may be best not have canned air around people who could be susceptible to misusing this type of product.

LensPen NLP-1

A lens brush.  You will need a anti-static brush to clean any dust the lens blower (or Dust Off) leaves behind.  LensPen makes a great brush – the NLP-1 ($9 USD), which is a double sided tool with a retractable brush on one end and a microfiber “pen” on the other end.  I do not recommend using the microfiber pen part, but the brush is very good and the fact that the brush retracts helps keep it clean when not in use.

Pancro Professional Lens Cleaner 4oz
Carl Zeiss Lens Cleaning Spray

Lens cleaning fluid.  OK, you’ve spent thousand of dollars on your lens and on your camera.  Please, only use the highest quality lens cleaning fluid.  Never (ever) use Windex or a similar detergent on your lenses!  I suggest buying some Pancro.  A 4oz bottle is about $20 USD and will last a very long time.  Can’t find Pancro?  Zeiss has lens cleaning fluid as well.   I do not recommend pre-packed lens cleaning wet wipes as they contain too much moisture which can find its way inside your lens.   Only one drop of Pancro is needed!

Kimtech Science KimWipes Delicate Task Wipers

Lens Tissue.  Never, ever use your shirt, or a wash cloth, paper towels or similar things to clean a lens.  You will likely scratch the optics when using these.  High quality lens microfiber cloths are used by some people however they also trap dirt, grease and debri over time which can seriously damage a lens.  Lens microfiber cloths also pose the problem of knowing which microfiber cloths are high or low quality.  If dirty, lens microfiber cloths can be washed and reused … but how many people are disciplined enough to wash their lens cloth?  A much better solution is to buy a box of Kimtech wipes.  Kimtech’s are dust free and when used with one drop of Pancro will not scratch your lens.  Kimtech’s  wipes are cheap enough that you can (and should) throw away a used tissue after each pass cleaning a lens.  A 280 count box is under $7 USD.

 

Rosco Lens Tissue 4″ x 6″

As an alternative to Kimtech, Rosco sells lens tissue in a booklet form ($7 USD) but the tissues are not very well protected.  If the booklet is sitting in your desk drawer or fanny pack, it can pick-up quite a lot of dirt on the tissue pages, which will then make its way onto your lens when cleaning (potentially scratching your lens).

PEC-PAD Lint Free Wipes 4″ x 4″

If you cannot find Kimtech or Rosco, a third option is Pec Pads ($13 USD).

Lastly, you will need a large freezer bag.  Grab a large Ziploc or Hefty freezer bag from your home, put all your lens cleaning supplies (except for the flashlight) in the bag for storage when not in use.  The freezer bag will help prevent transferring dust or dirt when in storage onto your lens cleaning kit supplies.

You should be able to put together a high quality professional lens cleaning kit for as little as $60 USD.

 

Other helpful things to keep handy

• A front lens cap for your lens
• A rear lens cap for your lens
• A cavity cap for your camera body

Lens Cleaning Steps

Step #1:  If the lens is removable, turn off the camera, disconnect the lens control cable from the camera body, disconnect any rear zoom or focus controls which may be attached to the lens, support the lens with one hand while rotating the lens mount locking ring on the camera with your other hand to remove the lens from the camera body.  Cover the camera body lens mount with a cavity cap.  Then cover the lens front and rear elements with their respective lens caps.  Lay the lens safely/securely on a table.

If you do not have a camera cavity cap, loosely tape a sheet of clean lens tissue over the camera’s lens cavity to avoid dust getting inside the camera while you are cleaning the lens.  Paper tape works well to keep the lens tissue in place over the camera’s lens mount and does not leave behind a lot of glue residue.

If the lens is not removable, turn off the camera’s power and proceed to Step #2.

Step #2:  Uncap the front element of the lens.  Using your flashlight, shine the light into the lens from various angles so you can see where the dust, dirt or finger prints may be.

Step #3:  Hold the lens upside down (whichever element you are about to clean pointing downward toward the ground), to insure that any loose particles fall to the ground and not back onto the lens. While the lens is upside down use the blower bulb (or Dust off) blowing air in circular motion at a 45 degree angle to the lens element.  Note that when using Dust Off only use short bursts of air.  Make sure not to aim the nozzle perpendicular to the lens or have the nozzle any closer than four or so inches from the lens.

Check the lens again using your flashlight.  If needed, repeat Step #3 again.

Step #4:  If dust, dirt or fingerprints can still be seen, rotate the lens now upright, gently using “the brush-end” of your LensPen and staring at the center of the lens, gently brush outwards toward the edges.  Do not jab the bristles into the lens.  Just gently sweep the lens from the center outward.  Check the lens again using your flashlight.  If needed, repeat Step #4 again.

Step #5:  When you are sure that all loose dust or dirt particles have been removed, take out the Kimwipes and throw away the top sheet (just in case it got dirty while in storage).  Remove the second Kimwipe sheet, fold it in half (or in quarters) and moisten it with one drop of Panchro (no need to soak it).  If your Pancro bottle has a spray nozzle, spritz the folded Kimwipe just once.  Never, ever apply liquids directly to a lens.  One drop of Pancro onto the Kimwipe is all you need.

Now, starting at the center of the lens and using tiny circular motions, gently wipe the lens in concentric circles from the center outward (like a LP or a 45 record, but in reverse).  It does not make a difference if you go in clockwise or counterclockwise circles.  When you get to the edge of the lens throw the Kimwipe you are using away. Check the lens using your flashlight.  If needed, repeat Step #5 again with a fresh Kimwipe and one drop of Pancro.

Step #6:  Using a folded dry Kimwipe, gently use the same circular technique to insure all liquid has been removed from the lens’ surface.

Step #7:  Clean the inside of the front lens cap and then put it back on the front element of the lens.  Now remove the rear lens cap and perform Steps #2 – #6 on the rear lens element.

Step #8:  Remove the camera’s cavity cap, remove the rear lens cap and remount the lens to the camera body.  Reconnect the lens cable and any rear zoom and focus controls.

Step #9:  Remove the lens’ front cap and verify the lens’ back-focus setting.  Here are steps to adjusting back-focus if you need a refresher.

If you follow these steps as part of a scheduled lens maintenance regime, you can be confident you are getting the best images possible out of your equipment.

Tom D’Angelo has worked in television production and AVL corporate theater for the last thirty-eight years. He has been nominated for a Mid-Atlantic Emmy Award (Best Director category) and has been part of various teams that have been nominated and won national Emmy’s. As the Media Director at a megachurch in the 1980’s he developed a love for the Church and church performing and technical artists.

Tweet
Share
+1
Share
Pin