DSLR Sensor Cleaning

Written by Mark Holmes on .

This week, I was at a client's photographing a number of product components, when I noticed a hair appearing in photos. I examined the lens I was using and found it clean, so the problem had to be on the senor filter. I gently wiped it with a Pec Pad and the hair disappeared, but there were still several smudges left, so today I decided it was time to give my camera a good cleaning.

It has been awhile since I thought about cleaning my camera sensor. My latest camera has a self-cleaning system, which basically means that the sensor vibrates when the camera turns on to shake off dust. It's fairly effective, but it doesn't get rid of everything.

Here is one of the later shots from the shoot, with an obvious smudge on the picture. It was easy to remove using the Photoshop Spot Healing Brush, but that's not the point. I want stuff like this out of my pictures, because it isn't always that easy to fix. There are other smaller blemishes on this picture too, which I had to deal with in Photoshop.

When the dust bunnies appear, it is time to do something about it. Cameras these days mostly have self-cleaning sensors, but that doesn't mean the system always deals with dust problems effectively. Nikon sensors now have a tin oxide coating to help repel the dust, so I did a careful search online before I decided it was safe to clean my D300 the same way I had cleaned my previous Nikons. Thom Hogan, who is a Nikon guru and a great technical writer, offered re-assurance that I was not going to destroy my cameras using the same cleaning technique I had always used.

I have always used the cleaning method with complete success described in tutorials by Copperhill Images. I checked their site out again and found that they now sell "sensor wands". In the "old days" we used cut down rubber spatulas, which I still use, and I am pretty sure that the method was recommended by Copperhill. I think since they've started selling their own special tool, they no longer recommend using your own tool to clean the sensor. I think their instructions are excellent, so if they want to make a bit of money by selling you their tool, good luck to them.

Looking through my supplies, I found my Pec Pads were contaminated and, as usual, the Eclipse fluid had dried up to nothing. It cracks me up how Eclipse can sell such a volatile solvent in a bottle that basically lets the product dry out within a few months. They have started putting a seal on the bottle, but that only works while it is on the shelf. I walked up the street to Nelsons and purchased everything I needed:

Eclipse optic cleaning fluid: $8.55
|Pec Pads: $8.55
Giotos lens cloth: $8.09
Dotline Big Blower: $7.16

Now restocked with my sensor and lens cleaning goodies, it was time to attack the sensor issue. I have to say, although the self-cleaning program doesn't do a perfect job, it it much better than nothing. I was always cleaning the sensor on my D70. I'm amazed that it's taken so long to have to clean the D300 sensor filter.

The next thing I did was to take a picture of the sky. (For those seeing this in England, the picture on the left is an unedited San Diego sky.) I noticed three distinct smudges, which had all appeared in my photos for my client.

Before even thinking about touching the sensor filter, the next thing to do was get out the blower and puff some air on to the problem. Most DSLRs have a function called something like "lock mirror up for cleaning".  Select this to raise the mirror and open the shutter so that you can see the sensor filter. You have to take the lens off, of course.

Once the sensor filter is exposed, you can give it a puff or two of air with the blower bulb. I really don't like canned air, because it squirts propellant and is also pretty harsh.

The picture left shows the result after using the bulb blower on the sensor filter. Just one obvious dust bunny left!

Oops! Feeling confident, I thought I'd get after that last dust bunny by blasting my sensor filter with another ounce of fresh air. Now, this appeared in my picture of the sky. I looked at the sensor and I think I saw a hair from my lens brush. I gave it several more squirts with the rubber bulb and blew it away.

Result! I didn't need to go to the Pec Pad and Eclipse solution, because blowing air cleared the issue. It's important to start with this simple solution before daring to touch that sensor filter!

I'm glad I didn't have to go to the next stage, but I am confident that I could have cleaned up the problem, if necessary.