About a year ago I bought an EOS 20D with the lens kit. Apart from when it came in the box, that lense has never been off the camera, so I couldn’t believe it a while ago when I saw a grey spec on images that kept occuring in the same place. (Admittedly it is tiny, but that sort of thing really bugs me)
When I took the lense off and fired the camera on a long exposure, I could see very clearly that there was some dust on it’s surface (or actually the low pass filter covering the CMOS to be precise)
After doing a bit of web research it seems that dust on DSLR CMOS is really common.
So what are my options? I think the guy at the shop told me to bring it back if the CMOS ever needed cleaning, but I can’t be sure. He said something about that.
Apparently the maufacturers recommend that cameras should be returned to them to have CMOS sensors cleaned, but from what I have read, it is expensive, takes a long time, and often comes back no better than before.
I appreciate that it is very risky to attempt a clean of the CMOS sensor yourself, but I am not sure if I trust a camera shop to do a decent job either.
Don’t worry, the process is easy. I use the Eclipse solution and swap method. It’s a bit scary the first time. But I’ve done it many times the sensor works fine. This is the only place I know in Taipei that sells the proper items needed is here:
Also, if your camera is under warranty, you can take it to Canon Taiwan (aka Rainbow Cameras) for free cleaning. They usually get it back to you in a day or two.
There’s no need to take it to the camera shop. Get one of those cheap, squeezable air blowers (definitely NOT canned air, though) from a camera shop. Fully charge your battery. Then go to Sensor Cleaning in the main menu. Select OK and the camera will shut off with the shutter open. Remove the lens. Put the tip of the blower as close as you can to the sensor without touching it and give it a few good blows. Replace the lens and turn it off. Takes less than a minute to do yourself.
There are some methods of cleaning that involve actually touching the sensor with some sort of brush. I’m wary of those simply because you could theoretically damage the sensor that way. Moreover, I’m constantly switching lenses and taking a lot of macro pictures, where the tight apertures and blurred backgrounds make the dust very obvious, and I find doing this method once every couple weeks to be more than sufficient.
Also, a good way to check to see if you’ve removed all of the dust specks is to take a picture of a blank wall completely out of focus with the aperture set high (at least f/16. Exposure time doesn’t matter.) The dust specks will be much more obvious.
And dump the kit lens. It’s like hooking up a $1000 electric guitar to a $50 amplifier.