How to Clean Your Camera Lens: The CIA’s Guide

Declassified is an original Phoblographer series that digs deep into historical documents to examine how the government used photography.

I’ve seen some pretty crazy things get recommended for cleaning lenses. A few years ago, Pop Photo said that Vodka worked. We’ve done a few demonstrations with Isopropyl alcohol. But a document in the CIA’s archive is different. Their approach is a lot more like what an eye doctor would say today about your glasses. One would wonder why a document like this needed to be written. Well, of course, someone was messing up big time. And cleaning lenses with anti-reflective coatings needed a reference document.

No one wants to be the reason why a protocol is made, but it’s common in companies when someone costs them a lot of money. And too many mistakes make things frustrating for everyone. Cleaning lenses is something we suspect most people don’t know how to do. For all we know, they probably used rougher cloths. Admittedly, I’ve had staff do things that have raised my eyebrows. From the looks of it, someone did too back in 1967.

In a 9 page document, we can analyze how much care the CIA put into coated lens optics. At some points, it feels like they’re explaining the process to a five year old. Page 2, for example, cites that this guide is only for coated lens optics.

They get into it by telling their agents to wear gloves or finger cots. Finger cots are a funny bit. Admittedly, the first time I saw them, I thought they looked like the weirdest STD protection I’ve ever seen. But they were heavily used in the darkroom. Once you’ve got those on, the CIA tells you to only grasp the edges of the lens.

Before I go on, remember that some of this sounds like it was written for children. They even detail something to the effect of not getting your filthy sweat on the lens optics. I’m sort of shocked that they don’t tell you to wash your hands. It really makes me wonder if someone used to eat cheeseburgers and then try to clean the lenses. And as a business owner, it makes me question their own hiring process. But that’s not for me to decide.

The document details the various imperfections. It discusses fingerprints, paint, dirt, etc. These are all things most modern photographers would deal with anyway. But first, you have to get it as clean as possible using air. So they talk about using syringes with air. These are predecessors to Rocket Blowers. But then they get into solvents:

  • Benzine is good for removing oil.
  • Warm acetone for some adhesives
  • Alcohol is fine
  • Liquid detergent is fine. This is otherwise known as dishwashing liquid in some cases. This is recommended with hot tap water.

Today, lens manufacturers have told us that the purer the alcohol the better it is for cleaning your lenses. My personal eye doctor has recommended soap and water. She also tells me to bring a micro fiber cloth with me everywhere. Her techs use a toned-down alcohol spray to clean my lenses when I get a check-up.

But most notably in this document, the CIA says that this isn’t easy to do. In fact, they sort of take a jab at inexperienced personnel who do this. We recommend you check out the document for yourself.