Lens fungus is a combination of dust and moisture that finds its way into the interior elements of a camera lens. Dust by itself does not typically cause a problem, but if that dust contains fungus spores and is combined with moisture, fungus can grow. It is more common with lenses that are not weather sealed and used in very humid, tropical areas. It can look like small web-like spots or patches inside the lens.
Left untreated, lens fungus can permanently decrease the performance of the lens and cause your images to look fuzzy or hazy.
Follow the steps below to check for lens fungus:
- Remove the lens from the camera.
- Make sure the front and rear lens caps are removed.
- Make sure you have plenty of light nearby.
- Look through both ends of the lens to see if you can spot any fungus growth.
If you suspect lens fungus, the lens should be evaluated a professional lens technician to determine if it can be cleaned.
NOTE: Lens fungus is not a condition covered under warranty.
After using the equipment in humid conditions, do not leave it stored in the camera bag. Make sure the equipment is fully dry before storing it away. It is a good idea to store lenses in a see-through container with silica gel packets if you are not going to use them for a long time. Since fungus thrives in dark, moist areas, storing the lenses in this manner will help prevent fungus growth. The silica gel packets absorb moisture while the see-through container allows light inside that can kill fungus.