Have you ever noticed little bits on your photos? Not the little crumbs from a cookie that help make the photo more real looking. But, little indiscernible dots or smudges or blobs that appear, usually if you are shooting something on a solid white background. That's dust. And, if you are using a dSLR, you probably have some on your sensor. Here's a quick way to tell. Close down your aperture as far as you can... probably somewhere around 22. Then take a properly exposed photo of something white. Any dust that is on your sensor is going to show up, and look something like this: The first image is at 100%. You can see two little light grey spots within the red highlighted area. The second box (below) is that red box zoomed in even further. If you look closely in the first box, right by the right edge, you'll see another dust bunny... a little squiggly do like thing. These little specks will appear in the same place on every single photo I take. Now how annoying is that? The good news is that there are many ways to fix this problem. First off, if there are just one or two spots, the clone brush in Photoshop or the spot healer in Lightroom will make quick work of them. The only time they are really noticeable (if they are small and light like these) is when they are on solid color backgrounds where they are also easy to fix. If you easily get weary of the manual dusting, SensorKleen is app that can do the cleaning for you. Basically, the software analyzes a batch of photos, and tries to find the common spots... then it can clone them out automatically. I tend to go the old-fashioned way, but if anyone out there has tried it and has feedback, I'd love to hear it. I've also heard that the software that Nikon ships with its cameras that has a dust removal feature. Of course, once it gets bad enough, you really do need to clean your sensor. There all manners of brushes and swabs created for this task. Personally, I'm terrified to touch the sensor on my camera. I tried to clean my view finder up one time and mucked it up... so I stay far, far away from the inner workings. Instead, I take my camera in 3 or 4 times a year to get it professionally cleaned. In Seattle, I can highly recommend CameraTechs who will clean a dSLR sensor for between $35 and $45 dollars (depending on the size... 5Ds are more than 20Ds). If you live near one of the Canon service centers in New Jersey & California, I've heard rumors that you can take it in there and they will clean it for no charge. Canon has started to introduce automatic sensor cleaning to its cameras, but early results have been not so good. Olympus's model seems to have faired better, so perhaps there is hope in the future for this technology. Until then, CameraTechs has a pretty regular customer in me.