The Itsy Bitsy Spider

Published September 24, 2014

We spend a lot of time here at Lensrentals getting dust out of lenses. Dust doesn’t affect an image, except in very rare circumstances, but people want their rental lenses to look nice and clean inside and out, and our inspectors check the inside of every lens with spotlights and send any dusty ones over to the repair department.

Yesterday one of the inspectors sent over a Canon 135mm f/2 L lens with a fairly unique note: “Contains a large dust chunk and the internal elements are scratched.” Now, we see a lot of scratched elements, but that really is pretty limited to the front and rear ones. Scratching internal elements is, well, unusual. When we took a look inside the lens, though, we were pretty impressed. There was indeed a big chunk deep in the center of the lens, and what at first glance appeared to be multiple scratches on the internal elements.

A closer look, though, showed that the “chunk” was actually a small spider. What the inspectors thought were scratches was actually a fairly complete web he’d spun inside the lens. The spider gave every appearance of being deceased – we assume because even a very nice spider web probably can’t catch much dinner when it’s inside a camera lens.

We did, of course, take some pictures with the lens, including some f/22 sky shots just to see if there was any way we could see it in an image, but of course we couldn’t. The pictures were perfectly normal.

We suggested that we leave the spider in place, call this the Peter Parker Special 135mm f/2, and charge extra for it. Management replied, “With great repair power comes great responsibility. Take the spider out.” So we did. Even though he wasn’t bothering anybody.

As you can see above, the front group of the 135 f/2 is pretty thick, which provides a lot of magnification. Seen from underneath the front group, our spider is actually quite small and not nearly as impressive as he appeared from outside the lens.

We had to break out a macro lens to make him look even halfway impressive. (Even then, he’s not as impressive as the dirt on our sensor at f/16, is he? I’d like to take a moment to point out that Darryl is in charge of keeping the test camera sensors clean.)

With a little side lighting, though, I was impressed how he’d spun a web across the entire rear surface of the front group. There’s a large air gap between the front element and the aperture, and he’d made a nice trapeze complex across that too.

We check around 500 lenses a day, 5 days a week, so we tend to see almost everything that you can imagine inside lenses. We’ve seen more than a few fruit flies, but this is our first spider and our first web, so we thought we’d share.

Roger Cicala, Aaron Closz, and Darryl Bolin


September, 2014

Author: Roger Cicala

I’m Roger and I am the founder of Lensrentals.com. Hailed as one of the optic nerds here, I enjoy shooting collimated light through 30X microscope objectives in my spare time. When I do take real pictures I like using something different: a Medium format, or Pentax K1, or a Sony RX1R.

Posted in Other
  • CiaranH

    Spider webs once had a useful place inside lenses: my father was an instrument technician, and he would use spider web to make the cross-hairs in gun sights and other optical instruments. Apparently the web was stronger and finer than could be achieved with other materials, and was in use up to the sixties. He would press any spider in the vicinity into service to make web. My friends thought he was a bit off when he would come home and say he’d had a hard day milking spiders.

  • This is not the first time I’ve heard of a spider messing up optics. Years ago I was doing a product demonstration in a university biology lab. While I was there, two techs from another company were servicing a real-time PCR machine (http://en.wikipedia.org/wiki/Quantitative_PCR_instrument) which was having issues with its fluorometer. It took them a while to figure out what was wrong, but they finally found a spider web woven across the detector’s optics. A little spider took down a >$50K instrument.

  • gandalfii

    Uh, the spider was most likely female.

  • Really Random Guy

    I seem to remember you had a Nanoha on the NEX. Could of been interesting to test it out on the poor little fella.

  • Roger Cicala

    It was, indeed, quite deceased. Rather mummified actually.

  • John Leslie

    You said the Spider appeared to be deceased, presumably after you opened up the lens you could confirm this?

  • Stephen Sells


    That’s pretty much how I imagined it. Running a business can be tedious for engineering minded and I didn’t picture you as an the iron-fisted CEO type.

    As long as you are having fun, it can’t get much better than that.

  • Remus

    I also had this happen with a Nikon 70-200/2,8 VR 1. The spider fell to one side of the lens after a while and small threads of web are still visible inside the lens, but it does not affect operation so i had not had it serviced. http://www.dpreview.com/forums/post/51553667

  • > Apparently aging without maturing, which I’ve always considered a goal

    A fifth grader informed my wife and I (50 somethings at the time) that the shortening of GRownUPS was … GRUMPS

    I try to channel Patch Adams, M.D.

  • NancyP

    This is a very small spiderling, probably got blown in or wandered in as a brand-new hatchling and starved. I assume it got there during the period of time that the lens was off the camera and the rear cap was not yet applied to it. Who would notice such a tiny wisp landing on the lens? (Just great, now I am going to be squinting at my lenses every time I get back from a nature shoot – grr.). No, I can’t speciate the tiny corpse from the macro shot. Bring out the PCR!

  • Aaron

    And fortunately we all benefit from your lack of adult supervision in the repair area by being curious and buying rather expensive optical testing gear. Gives us all sorts of great posts 🙂

  • Helmut

    Canon always claims to use environmentally-friendly glass …

  • Roger Cicala

    I did start the company. Starting things is what I’m good at. But I found out (slightly the hard way) that me and a few other people starting cool things is very, very different than managing 80 people, handling depreciation and taxes, negotiating lines of credit and other stuff that takes more than my 20 minute attention span. So I let people who understand business run the business (and they own a slight majority of the company now).

    Don’t think Steve Jobs, think Steve Wozniak, who after Apple went public just wanted to go back to his cubie and be an engineer. I stay in the repair area in jeans and T-shirt and play Rocket Surgeon while the business people run the business. Once a month at the stockholder’s meetings I act like an owner, otherwise, I just stay in my cubie and play engineer.

    So, while I don’t deny talking to imaginary friends every so often, there is a real entity that clamps down on my fun loving nature and provides adult supervision. (My ex-wife also tried to provide adult supervision but she gave it up as a thankless task some time ago. Apparently aging without maturing, which I’ve always considered a goal, does not make one successful in either business nor relationship management.)

  • Stephen Sells

    I often wonder when Roger refers to “Management.” Didn’t he start this company? I assume one of a few different options:

    1. The bean counters that he has placed over him to provide some needed adult supervision to the business.
    2. An imaginary entity used as a foil to clamp down on Roger’s fun loving nature and bring the necessary conflict that all great narratives need.
    3. An evil Board of Directors that will eventually fire him Steve Jobs style and turn LensRentals into a giant soulless lens processing machine.
    4. His wife.

  • John

    Just goes to show that not all aberrations (bad web geometry) are caused by lens-sensor interface.

  • Looks like “Peter Parker” was on caffeine while spinning his web…

  • Nqina Dlamini

    “With great repair power comes great responsibility.”
    Thank you, I had a quite laughed.
    I wonder how he got in there. Probably got de-hydrated and starved to death poor thing.

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