Cleaning Lenses

Clean lenses as NEEDED. There are chemicals on the glass optics that you can rub out. So, be judicious when you clean a lens. Often times blowing out the dust is all that is necessary.

You will often see dust on the lens because dust is everywhere. Try to resist cleaning the lens unless there are fingerprints/smudges/grime on the glass. Try to use the rocket blower or the blower brush first. Note that a little bit of dust will not impact the image.

GENERAL STEPS:

1. Take off the cap from the front element of the lens. Blow the dust out of it by pointing the inside of the cap down and blowing up into it.
2. Remove dust from the front element of the lens with the blower/blower brush first (again, point the lens down and blow upwards). You can also blow air onto the lens with your mouth to get rid of dust, but do not breathe hot air onto it.  If you do not remove the dust from the glass, you could scratch the glass by rubbing dust into it while doing further cleaning.
3. Use a bit of lens cleaning solution on the lens glass. If using cleaning solution, apply it to a lens tissue and NOT the lens itself. In a circular clockwise motion, rub the tissue on the glass and work your way from the center of the glass to the outside. If using the microfiber cloth, rub the cloth in a circular, clockwise motion from the center to the outside will get it clean. Do NOT blow hot breath on the lens as it will eat away at the coating. BE GENTLE WITH THE RUBBING; it’s not a scrubbing activity.
4. Put the cap back on the front element. Inspect the rear element of the lens. If it needs cleaning, repeat the previous steps on the rear glass element. Never take the cap off the front and rear elements simultaneously, as you will blow dust onto the side you just cleaned.

 

NOTES ON CLEANING: 

For Microfiber Cloth and Tissues:

• Use a lens tissue only once and then discard it.
• The microfiber cloth will get dirty. If it gets dirty, please notify your supervisors so we can clean it.
• We have some cotton swabs. They are great for cleaning around the edge of the lens.

Using the Blower:

Always blow the air up with the surface you are trying to clean pointing down. This will allow the dust to blow out and fall. If you blow down, the dust will shoot into the air and could fall back down onto the lens.

 

Cleaning Under the Filter:

All of our lenses have a clear, UV filter on them. This is to protect the front glass of the lens. So, 90% of the time you will be cleaning the filter. However, if you clean the filter and notice dust or grime on the actual glass or between the filter and front element, follow these steps:

1. Gently turn the UV filter counterclockwise to remove it. If it’s stuck, take a thick rubber band, wrap it around the filter, and turn it counterclockwise (pictured below).
2. Blow dust from and clean both sides of the filter.
3. Blow dust from and clean the front glass on the lens.
4. Align threads of the UV filter with the lens’s female threads. Gently turn clockwise. DO NOT force this. You want it on there secure but not super tight. Contact a supervisor if you encounter any issues.

THINGS YOU DON’T DO!

1. Never breathe hot air onto a lens.
2. Never use a t-shirt or cotton to clean a lens.
3. Never re-use a lens tissue.
4. Never use a dirty microfiber cloth.
5. Never use Windex or any similar product to clean the lens.
6. Never wipe a lens before you blow off the dust.
7. Never use canned air.
8. Never use the blower to clean dust out of the camera body. Dust on the mirror is fine; it will not affect your image as it pops up. But blowing dust off the mirror will blow it onto the sensor and that can be a major issue.
9. Never clean the sensor. If you feel that there is dust on the sensor, speak to a supervisor.

 

This page was written by Andre´ Sirois for the University of Oregon Cinema Studies Program and is published under Creative Commons license (CC BY NC SA 3.0)