A few weeks ago, I did a terrible thing to my camera. I made things worse by trying to fix it, to the point where the guy at the repair shop look visibly shocked and advised me to buy a replacement. This is the story of what I did, and how I fixed it at no cost. I own an entry-level DSLR camera that I use for family photos, forgettable landscapes of the hills outside my home, and astrophotography. It is a Canon EOS 1100d, which came with an 18-55mm kit lens, and was very cheap when I bought it. It has given me some quite lovely astronomy shots, and is frankly overpowered for all my other uses, so I’m very happy with it. However, over time, the lens has picked up a fair number of fingerprints and greasy smudges. This is what happens when you take pictures of children and pets. Recently, it picked up a particularly bad thumbprint, thick enough to give a noticeable blurry spot in my photos. It was time for a cleaning.
But this thumbprint was a real problem, so I did my homework. It turns out that most recommended camera cleaning methods only deal with dust, and removing grease (including fingerprints) is considered a major job. The recommended tools are usually special papers or cloths, lightly damped with either a VERY dilute solution of detergent and distilled water, isopropyl alcohol, or specific brands of lens cleaning fluid. So I looked around the house and found what I judged to be suitable equivalents: Cotton balls and surgical spirits.
Experts advise against cotton balls because they tend to leave fibers behind, all over your freshly cleaned surface, but I was not particularly bothered by this. I can deal with fibers. The surgical spirits gave me pause, mainly because I was unable to find out what exactly goes into the stuff, but I had enough experience with it to be sure that was simply a very strong alcohol solution, probably in the order of 95% by volume. So I took a cotton ball, dipped it into my bottle of surgical spirits, squeezed it out, and wiped it lightly across the fingerprint.
The result was beautiful – clean, dust-free, smooth, no blemishes. A perfect optical surface and best of all, the lens coating remained a dark shadowy violet, with no streaks or blemishes. All was right with the world. Until, as I watched, that beautiful arc of glass suddenly fogged over. I repeated the process, with no change in results. My lens, which had previously had a bit of dust and some fingerprints, now looked as if it had been smeared with Vaseline. Disaster.
Loathe to do further damage, I dried the lens with cool air and capped it. What to do? I pondered for several days, determined not to make things worse by rushing headlong through a series of mad fixes, until while picking up some groceries at the local mall, I spotted a camera specialist. These people were official Canon dealers, and would know what to do. So I told them my sad story to the guy behind the till, and his face actually went pale. He stammered a bit before asking what made me do such a silly thing, and had no advice to offer beyond “Bring it in. We’ll have to ship it back to the factory, and hope they can do something about it”.
Now I knew I’d made a silly mistake, but I also have a pathological mistrust for salesmen, and I strongly suspected that the young man in the camera shop was working a pitch on me. And anyway, I know that what he was proposing is a costly process – shipping plus repair costs can come to a lot of money, probably more than it would cost to simply by another kit lens on the used market. So I went back to the internet, this time with a query specific to my problem. Lo and behold, it turns out that surgical spirits is 95% ethanol, with the remainder made up of varying amounts of water and castor oil. This is because it is intended for medical purposes, which mostly involve rubbing it onto the skin. The oil is to prevent the skin from drying out.
So basically, I oiled my camera lens.
I had no idea what to do about this. My first instinct was to use detergent, but I wasn’t confident that it would work. After all, the detergent would lift the oil from the surface (probably) but what would it do to the optical coatings? And how could I be sure that the oil would then transfer to the tissue paper, and not simply settle back on the glass as the solution dried? It’s not like you can immerse the thing, and rinse it off, after all…
So I took a chance. I bought a micro-fiber cloth, one specifically marketed as being ideal for cleaning drinking glasses, spectacles, computer screens, etc. And after inspecting the lens surface for dust, carefully (oh so carefully) wiped it with the dry cloth.
And after less than five minutes, all the visible oil had been absorbed into the cloth. Amazing. I’ve fitted the lens back onto the camera body and taken a few test shots, and the images are as crisp as ever (which is to say, not very – it’s not a very expensive lens, after all!).
So if you ever end up in the same situation as me, needing to clean a lens, learn from my experience: don’t use surgical spirits. Get proper optical grade isopropyl alcohol. Or better yet, pay a professional to do a proper job. You probably won’t be as lucky as I was.