There comes a time in the life of every photographer when cleaning equipment becomes necessary. Dust has a way of accumulating and there is nothing that can be done about it except regular maintenance. One of the most important parts of the cleaning process is the digital sensor. Even if you never take the lens off the camera body, somehow, some way, dust is going to find it’s way into the camera body and it never settles anywhere but on your sensor where it will show up on your photos. If you do switch lenses like most of us, you’re going to get dust in your camera. Either way, eventually, it’s going to become noticeable. First to you and then to your clients, and you never want to let it get that far.
There are two ways of becoming aware of dust: the first is when it shows up in your photos, which is the worst way of all. The second way is through regular maintenance, and that is what this blog is all about: cleaning the sensors on your cameras regularly and how to go about it.
Once you’ve removed the lens from the body of the camera, you’re going to notice an obstruction: the mirror in your camera. Some of the better manufacturers, such as Canon, have a “sensor cleaning” selection built into the menu that will automate the process of lifting the mirror out of position so that you can gain access to the sensor, but if you don’t have that, it is simply a matter of putting your camera on “B” or Bulb setting and hitting the shutter release which will allow for an unlimited exposure. It flips up the mirror and exposes the sensor, staying in the open position until you hit the shutter release button once more.
Don’t Ever Use Compressed or Canned Air on a Camera!
The reason for this is that the force of air from a can or compressor will not only cause damage to moving parts, but, particularly with canned air, whatever chemicals are in the can will often leave damaging splotches of residue behind. So stay away from them. Don’t learn this the hard way! What you want is one of those brushes with a “bulb” attached that will allow you to “blow” air by squeezing the bulb. There is more than enough pressure to dislodge dust with it. If you are going to use the brush, be very careful not to use the brush on the sensor. No matter how gentle those brushes are, there is always the potential for scratching the surface of the sensor. By the way, in most good DSLRs there is a cover to the sensor, so you don’t actually touch the surface of the sensor itself. It’s like having a UV filter on a lens, but even having to send the camera in to replace that “filter” is no fun, so be very careful with those brushes.
What to Look For in Sensor Cleaning Kits
There a number of very good sensor cleaning kits out there, so there’s no need to get into a discussion of which one to buy, but there are certain things to look for when you do. Most of the better kits will come with several “brushes” that are presoaked with a lens cleaning solution, or at very least a bottle of solution that you can apply to the brush. These brushes are a swab cloth that is wrapped over a plastic mold with a handle that is the same width as your sensor, or even smaller. Be sure to buy a kit that has these swabs wrapped in their own plastic sheathes. You want them to be hospital clean when you buy them and it’s always a good idea to wrap the remaining brushes inside a plastic sandwich bag that seals tightly to avoid contaminating the brushes. There should be several brushes in each kit. Unwrap an individual brush and on an angle to the sensor and gently drag the brush across the sensor, then turn the brush over and repeat the process in the other direction. Then throw away the brush. You do not want to use that brush a second time, especially if it might have some dust on it. When in doubt, always read the manufacturers instructions carefully. The camera you save may be your own!
Lastly, get the mirror back down, or if you have an advanced DSLR, push the shutter and restore your camera to its usual settings and put a lens back on.
Test your accuracy in cleaning by shooting off a few frames of the sky or some other monochromatic field that will display only one shade of gray or color. A blue sky is perfect. Spots and dust show up will against a single backdrop. Scan the photo on your computer to make sure you got everything. Repeat the process if you have to, using a fresh brush. If a spot or speck persists after several cleanings, take it to a repair shop to have the sensor looked at by a professional.
Take the time to regularly clean your cameras and they will reward you with extra time away from a computer cleaning up spots and dust digitally, which, if you are processing a lot of frames, will save you enormous amounts of time and energy that you could be better spending elsewhere.