Automatic dust removal
Starting with the Canon EOS 400D DSLR (Rebel XTi in the colonies), Canon has joined Olympus, Pentax and Sony in featuring ultrasonic dust removal (Automatic Sensor Cleaning) as part of their DSLR architecture. In addition, Canon's standard RAW converter (Digital Photo Professional – DPP) have the ability to map out dust particles (Append Dust Delete Data) in software.
In his Rebel XTi first impressions Michael Reichmann says it “seems to do its job well”. But Reichmann only had a access to the camera for a few days – not really enough time for dust to accumulate on the sensor – and there is no indication that he looked very hard for dust. Just glancing at some frames and concluding: no dust – so it must work, is IMHO worthless.
On his blog on AOL (no longer online), seasoned photographer Bill Hilton took a different view after trying the EOS 400D for a longer period. Here is a summary of his findings:
- Canon's ultrasonic sensor cleaning function does not work very well.
- Canon's dust removal software does a good job.
- To use this software, one must use Canon's DPP RAW converter, which might interfere with your workflow if you prefer another RAW converter.
Sony does not seem to do better. In the July 31, 2006 edition of ePhotoZine there is a review of Sony A100 that compares the automatic dust removal feature of the A100 with Olympus E-300. The verdict: “After five cleaning cycles the [Olympus] SuperSonic Wave filter appears to be much more effective than Sony's solution as it has removed much of the dust from the sensor surface.”
Hungarian website PixInfo has compared four brands that offer automatic senor dust removal. Their verdict on effectiveness: Olympus: 50 %, Canon: 5 %, Pentax: 0 % and Sony: 0 %.