Wednesday, 7 February 2007

Digital SLR Sensor Cleaning – Copperhill Set

If you are using more than one lens on your SLR you will sooner or later experience two issues.

1) Visible dust particles when looking through the viewfinder
2) Dust bunnies (spots) on your photos


Cleaning the inside of a digital SLR is the ‘open-heart surgery’ of photography. You can get it done by a professional service for about 100$. All camera manufacturers recommend to NOT do it yourself. If you scratch the sensor, you will have too carry the repair costs yourself.

On the other hand, it is doable. If you use more than one lens with your camera, you will need to get it cleaned regularly. After a lot of research I decided to get the procedure done myself. The below worked for me, but of cause it’s your own decision and risk.


A few tips upfront
  • Clean your camera in quite room on a clean table. No kids, dogs, cats around. Lots of light, no open windows/ wind.
  • Read the instructions in your camera manual and cleaning equipment ay least twice before you start!


1) Visible dust particles when looking through the viewfinder
These particles do not show up in your photos. The dust is most likely on the focusing screen below your pentaprism and above the mirror box in your camera body.

Ignore it as long as you can. Otherwise use a sensor brush and clean it very very carefully/ gently! I managed to remove two annoying large particles quite quickly.

Once you take the lens off, you will look directly at the mirror. The focusing screen is ‘ above’ (towards the built-in flash). See an illustration here: http://en.wikipedia.org/wiki/Single-lens_reflex_camera

Never try to clean the mirror. The mirror is front-silvered and gets scratches easily. Do not touch it. Use a manual blower to blow any dust off. It is does not come off, ignore it!



2) Dust bunnies (spots) on your photos

Dust on your sensor will result in visible spots on your photos. These are more visible in bright areas of the photo. And in photos taken with a large f-stop. Take a photo at f22 from the sky and check the photo. at 100% in Photoshop. Apply auto-level and it will become even more visible. See sample photos below.

To clean the sensor, you must put your DSLR into ‘cleaning mode’. For the Canon 20D this is done via the menu ‘sensor cleaning’. Read your manual! This will lock up the mirror so that you have direct access to the sensor. Once you take off the lens, you are looking directly at the sensor.

Actually your are not touching the sensor itself as there is a glass cover on top of the sensor.

One big warning here: If the power shuts down the mirror will come down and crash into anything what is in it’s way. Make sure you have sufficient battery life. Tape off the memory card compartment, opening it will shut down the 20D! Tape off the battery compartment. Put a stripe of tape over the power switch after you turned the camera on. Make sure you have a roll of scotch tape around and do the above at all times!


There is special equipment available to clean DSLR sensors. I used the Copperhill set. Find the details here. http://www.pbase.com/copperhill/ccd_cleaning

In Australia you can get it here: http://www.qualitycamera.com.au/product_info.php?products_id=1359

You might also want to read: http://www.luminous-landscape.com/reviews/visible-dust.shtml


Sensor after a year with no cleaning :-(

sky at f22


After swiping the sensor once, the test shot looked like this. 1 spot left.

sky at f22


Take Care!

1 comment:

willcowan said...

Hey i was googling for help on cleaning my sensor after a few weeks cycling in nepal and laos. The bangkok canon service centre in the mdk centre cleaned it for 535 thai baht. Thats about 17.50 aud. Quite a good deal.