Sensor Cleaning – Part 2

If you have not read part one, it would be a good place to start.

So, if you have “sticky” dust on your sensor that does not come off with the camera’s built in “Sensor Cleaner or Shaker” what are your choices? Before we start, I feel I need to insert a disclaimer –  Before you dig or poke into your $500.00 – $5000.00 camera, be sure you understand what you are doing.  It isn’t rocket science, but repairs are expensive!

Thom Hogan (the author of the tutorial I link to at the end of this post) says it this way: “My legal counsel wants me to run even longer legal disclaimers than Nikon, but I’ll keep it simple: when you work on your own camera, you do so at your own risk. I try to provide accurate, useful information that reflects how I work, but I can’t be held liable for what you do with that information. Use the procedures listed here at your own risk.”

If you are ready to charge ahead, here are some steps that can be used to remove dust:

1. First, try blowing the dust away.  Although this is a relatively safe procedure, there are some rules to follow:
   Don’t ever use compressed air, either from a can or a shop compressor.  The problem with canned air is the propellant. If the can is shaken or tilted it is very possible to spray some of the propellant onto the sensor cover.  The oily propellant residue can damage the cover and be very difficult to remove.  Oily residue is also likely from almost any mechanical air compressor. Even oil free compressors often put more dust into the camera than they blow out.
   A bulb type blower is the best solution.  One of the best is the Giottos Rocket-Air, but there are other brands.  If the blower has a metal tip be sure to add a short piece of plastic hose over it to prevent accidental scratches to the camera’s sensor cover or mirror.
   Speaking of mirrors, when you remove the lens from your DSLR you are going to notice that the mirror (and shutter) block the sensor.  It is a good idea to blow dust off the mirror, but you are going to need to get it out of the way & open the shutter before you have access to the sensor.  Check your camera manual for the method the manufacturer suggests for getting the mirror & shutter out of the way for cleaning.  It is very important to follow the directions.  If the shutter or mirror closes on the nozzle of your blower you are going to have a very expensive repair bill.  In most cases the manufacturer has a specific menu item for cleaning that prevents cleaning with a low battery or other mistakes that could cause problems.
   After a few strong puffs of the blower, put the lens back on the camera & shoot another test shot. Compare to see if you have improved the picture.  If not, try again.  If the spot moves around, blowing will eventually get rid of it.  If it stays in the same place, you are going to have to go to the next steps…
2. Send the camera back to the manufacturer.  In the case of point & shoot cameras, this is really the only option, however since they rarely end up with dust on the sensor P&S owners are unlikely to need to do this.  Returning the camera to the manufacturer has its good points – The dust is not really on the sensor; it is on a low pass filter that covers the sensor.  The filter is a very thin piece of somewhat fragile coated glass. Depending on what technique you use to clean the glass, it is quite possible to scratch the surface which will require an expensive repair. Particles of dust that look huge in your image are invisible to the eye, so it is difficult to immediately tell how effective your cleaning has been. Another advantage or returning the camera to the manufacturer particularly if it is still under warranty is they often “tune up” the rest of the camera, updating the firmware, cleaning everything, even replacing worn parts. The problem with sending your camera to the manufacturer is the loss of use while it is gone and, of course, the cost. In addition, obviously you can’t “fix” the problem while in the field.
3. Take the camera to your local camera store & let them do it. Whether this is a good idea depends on your local camera shop.  If it is a real one that has a knowledgeable technician, it will be far faster & less expensive than the manufacturer.  If they hand the camera off to some kid in the back room it may come back worse than when it went in. It boils down to trust – a good shop can do the job, a bad one can’t. It also requires a trip to the camera shop – if you are on a photo safari that isn’t going to work!
4. This is the big step – wet cleaning.  First, it is worth pointing out that done improperly, you can do a lot of damage wet cleaning a DSLR sensor.  On the other hand, if a blower doesn’t remove the dust, wet cleaning is about the only way to field clean your sensor. If you discover dust while on the road, cleaning it yourself may be the best option.  The process is simple.  You purchase sensor swabs designed for your camera, add a couple of drops of cleaning fluid (again designed for your camera) to the swab & wipe it across the sensor.  Again, if you are at all nervous about poking around in your camera (and you should be) try to do this the first time with someone who knows how to do it looking over your shoulder. It isn’t all that difficult, but you are scraping against the heart of your camera! The swabs are not inexpensive.  A package of 6 sensors & a bottle of fluid sells for anywhere from $30.00 – $45.00. They are usually put together in a clean room, and sized for specific sensors.  The fluids are also selected for specific low pass filters – be sure the fluid you use is correct for your model camera. Follow the directions for swiping the sensor.
5. There are some alternatives to wet cleaning.  Sensor brushes are said to work well on all but the most sticky dust; there are sensor cleaning sticks and a number of alternative techniques you will find by doing an internet search – I have not used anything other than a blower & wet cleaning so I can’t recommend any of the alternatives. Be very wary of some of the suggestions you might find.  I have seen suggestions of using the sticky side of Scotch Tape, “Q” tips, and others that at best will make things worse and could permanently damage your camera.
6. A good overall tutorial on the entire process is at the bythom web site: Cleaning Your Sensor. By the way, this is a great website for tutorials & DSLR information.

It pays to learn how to clean your sensor yourself.  It will save money, time, and can be done in the field.