Covering the technology, gear and talent behind film and video production

You say your lens went swimming?

Patricia Greene  August 21 2014 03:26:00 PM
You say your lens went swimming?

By Rich West

It happens in real time; so quickly you can only watch as that lens, which costs many thousands of dollars, plummets to the floor.  An expletive escapes as you attempt to stop the lens mid-fall but, alas, you just aren’t fast enough to overcome Newton’s Law.  There’s that horrible feeling in your gut as you watch the lens hit, and maybe bounce a time or two, because you know you are the responsible party: How are you going to explain what happened?

OK, look on the bright side.  Maybe it’ll only be a few parts that need to be replaced.  It’ll put the lens out of service for a while, but the lens will most likely go on to live another day.

Now let’s take a look at the “Dark Side”.  Instead of the lens landing on the floor it lands in the drink.  No, not that drink. (You know, the one you’ll probably have to calm yourself after “The Drop”).  The drink I’m referring to is that body of water that covers the majority of the planet:  sea water.  Unlike a fresh water pond or river, sea water has an element that just doesn’t mix well with lenses.  Sodium Chloride (NaCl), otherwise known in its common term as SALT.  NaCl, aluminum and brass don’t go well together.

While dropping a lens into a fresh water pond or river is reason enough to cause the onslaught of anxiety, it’s generally not the end of the world.  The lens can be shipped in a plastic zip-lock bag to a repair facility where technicians will dismantle the lens, clean it as they go, check for parts that may need replacing, and then reassemble the lens to factory specs.  Hours of work, and maybe the cost of some parts but the lens will likely live to work again. Not too bad, considering.

On the other hand, if the lens was dropped into salt water (ocean, salt water aquarium, brine tank, etc.) more severe challenges await.  The salt water must be promptly flushed from the lens or corrosion will set in.  “What”, you exclaim, “Put the lens in more water?” Yes! Not only put it in fresh water, but thoroughly flush it with fresh water to try and displace as much of the salt water as possible.  After doing this, seal the lens up in a zip-lock bag and immediately send it off to the repair facility with a big note providing notice of what happened and what steps you took.  Delays here will only make recovery more unlikely.

Maybe, if you’re lucky, there will be minimal damage.  Yes, there will probably be parts that have to be replaced, and there will be many hours of billable time for the technician to strip the lens down to individual parts, to wash each and every one of them in fresh water, and to carefully dry them so they don’t rust and/or corrode.  And, again if you’re lucky, the technician will provide you with an estimate of what the charges will be to put everything back together again instead of announcing it was a total disaster and loss. Unfortunately, because of the nature of the “accident” the technician can’t provide you with a warranty on the service he’s performing.  You sigh, as you realize you won’t have to buy a new lens; but if the lens was insured, you’ll probably now have to pay higher insurance rates due to the claim you file.  Life goes on.

To illustrate the disastrous effect salt water has on lenses, take a look at some photos of a lens that wasn’t flushed with fresh water and wasn’t sent immediately in for disassembly and service.  Not a pretty sight.


Image:You say your lens went swimming?

Front of lens showing sand and heavy deposits of salt

Image:You say your lens went swimming?

Visible are heavy deposits of caked-on salt

Image:You say your lens went swimming?

Salt and sand are everywhere

Image:You say your lens went swimming?

Salt has had time to work on the brass

Image:You say your lens went swimming?

Caked-on salt deposits

Image:You say your lens went swimming?

No hope for this iris


This lens was not repairable: i.e., a total loss.