DEALING WITH FUNGUS IN THE LENS
The dreaded fungus is something that bothers every photographer. I have suffered from it before, and every coming rain gives me constant worries of possibilities of fungus growing somewhere inside my lenses. I am more vulnerable to fungus than most people because I don't think much about taking out the camera to get some good shots even if it has been raining a bit, and have often got plenty of rain drops on the camera and the lens therefore.
The first time I saw them was on my 70-300 kit lens that I got removed for minimal cost. I was then using Silica Gel, but it had not helped me much. I have now moved on to using L glasses and was hoping that they are well weatherproofed enough to prevent fungus. But alas, not so! After 2 months of inactivity in the rainy days, I opened the lens last week and was depressed to see the first signs on fungus inside the glass. It was my 100-400L this time. It was just beginning to show a few small lines at one edge of the glass. Luckily it did not look like it would affect the images. And fortunately my other lens, 17-40L was intact.
I was going to be out for two days last weekend and that's when I saw the fungus on the lens. I had read somewhere in a photo forum that exposing the camera to sunlight will kill fungus. And fortunately it was sunny last weekend. While I used the lens often through the weekend, I exposed the lens to the sun when I was not photographing. I left the lens cap open even when I was not shooting and occasionally exposed it to the sun. I had to do this carefully and intermittently, since a telephoto lens can converge sunrays and cause lot of heat. Sunday night when I came back home, I had a look at the lens again. To my surprise, fungus seems to have mellowed down to an extent that it was difficult to see it unless I closely inspected it! Lucky for me, I think that has saved me a lot of money and the trouble of going to Canon service center.
My tryst with fungus has made me do some research on preventing them and getting rid of them in the last one year. Here are some of the methods that I have come across that people seem to use.
1. Silica Gel. This seems to be the easiest and common way to avoid fungus, but I haven't had much success with it either.
2. Store the lenses in an airtight container. Again, you may need to put a few Silica Gels in the container. Putting too many of Silica Gel is known to dry out the lubricants in the lens, so you need to use your discretion with quantity of the Silica Gel.
3. A popular idea is to install a low wattage tungsten bulb in the closet where you keep the lens. This will keep the place warm and dry, preventing the fungus. This is known to work.
4. Store the lens in transparent container. Fungus is known to fear light and love darkness. Also make sure that the lenses are not stored in leather bags, as leather can easily attract fungus.
5. And finally, of course, the best way to prevent fungus is to get out and shoot more often.
The first time I saw them was on my 70-300 kit lens that I got removed for minimal cost. I was then using Silica Gel, but it had not helped me much. I have now moved on to using L glasses and was hoping that they are well weatherproofed enough to prevent fungus. But alas, not so! After 2 months of inactivity in the rainy days, I opened the lens last week and was depressed to see the first signs on fungus inside the glass. It was my 100-400L this time. It was just beginning to show a few small lines at one edge of the glass. Luckily it did not look like it would affect the images. And fortunately my other lens, 17-40L was intact.
I was going to be out for two days last weekend and that's when I saw the fungus on the lens. I had read somewhere in a photo forum that exposing the camera to sunlight will kill fungus. And fortunately it was sunny last weekend. While I used the lens often through the weekend, I exposed the lens to the sun when I was not photographing. I left the lens cap open even when I was not shooting and occasionally exposed it to the sun. I had to do this carefully and intermittently, since a telephoto lens can converge sunrays and cause lot of heat. Sunday night when I came back home, I had a look at the lens again. To my surprise, fungus seems to have mellowed down to an extent that it was difficult to see it unless I closely inspected it! Lucky for me, I think that has saved me a lot of money and the trouble of going to Canon service center.
My tryst with fungus has made me do some research on preventing them and getting rid of them in the last one year. Here are some of the methods that I have come across that people seem to use.
1. Silica Gel. This seems to be the easiest and common way to avoid fungus, but I haven't had much success with it either.
2. Store the lenses in an airtight container. Again, you may need to put a few Silica Gels in the container. Putting too many of Silica Gel is known to dry out the lubricants in the lens, so you need to use your discretion with quantity of the Silica Gel.
3. A popular idea is to install a low wattage tungsten bulb in the closet where you keep the lens. This will keep the place warm and dry, preventing the fungus. This is known to work.
4. Store the lens in transparent container. Fungus is known to fear light and love darkness. Also make sure that the lenses are not stored in leather bags, as leather can easily attract fungus.
5. And finally, of course, the best way to prevent fungus is to get out and shoot more often.
posted by Arun at 8:56 PM
1 Comments:
Hi - i read your preventatives and thought i would add a word of help - and this comes from Carl Zeiss's site on lenes and fungus.
Fungus On Lenses
Fungus means an Infestation of optical instruments with fungus spores which germinate and produce more spores.
Lens surfaces are irreparably damaged by metabolic products of the fungus (e.g. acids). Its damage ranges from cloudiness to opacity caused by the film. The Carl Zeiss T* coating has no significant influence on fungus growth or generation of spores.
Where does fungus come from?
Fungus spores are everywhere and germinate under suitable environmental conditions:
Growing conditions
Relative humidity of at least 70% (more than 3 days)
No or little airflow
Darkness
Nutrients (textile lint, traces of grease, varnish, dust and dirt)
Temperatures between 10 and 35°C
How can fungus be avoided?
Reduce the relative humidity to less than 60% (never under 30% as it is dangerous for the instrument) by storing:
in climate-control cabinets in which hygrometers maintain environmental conditions
next to driers (e.g. silicagel orange packs) in the containers
in a special cabinet whose interior is heated to 40°C (max. 50°C) using a fan heater/ incandescent lamps, thereby reducing the relative humidity
in hermetically sealed cabinets with fungicides with high vapor pressure (fungicide depot must be replaced at regular intervals)
in an dehydrator above driers
After the work is done, Immediately clean the instruments. If possible, you can use a fan to facilitate evaporation of surface moisture. Do not use containers made of leather, textiles or wood for storage. Short solar radiation or irradiation with UV light may also help avoiding fungus.
How can fungus be removed?
Note: In general, Carl Zeiss does not accept instruments infested by fungus.
Clean affected surfaces with a cotton wiper that has been soaked with a disinfectant or fungus cleanser. You can build your cotton wiper, using cotton wrapped around a toothpickin such a way that a ball with a peak forms on the pointy end of the stick. Use pure cotton, no prepared or impregnated cotton. Strongly rub slightly corroded optical surfaces with an optical cleaning cloth, cigarette ash can be used as a polishing aid. Heavily corroded optical surfaces must be replaced. Fungus infestation in the interior of an instrument can only be eliminated through disassembly of the instrument.
Notes In addition...
i would note that it has been recommended via another site (which i can't remember at the moment) of a success story of removing fungus with a small amount of Hydrogen Peroxide and Anmonia at a 50/50 mix -
(tablespoon of one and a table spoon of the other mixed) and using a cotton tipped swab to aply to the infected lense.
Then rinse with a lens cleaning solution or water and finally using a micro cloth.
It may take a couple of times they mentioned but should work as they showed an example of the success.
Make sure when storing you have air flow... a point i remember from some where on the web...
Hope this helps anyone reading.
chase
c_canade@yahoo.ca
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