Unfortunately, problems with "dust blobs" in the AE2000 is not dust behind the lens. It is dust on the LCD and polarizers which lie some distance behind the lens. A speck of dust appears as a "blob" because it is substantially out-of-focus and not in the same plane as the LCD itself.I hope You have not gone in with the canned air before you've had a chance to consider using a vacuum instead. If your DLP or camera, projector, etc. has dust behind the lens (first place to try) hopefully it is behind the lens. Blowing the equipment clean is always a good idea and with expensive equipment it may be best to leave that for professionals but if you want to clean out a few pieces of dust or debris it will more likely be quicker and easier to vacuum. Little chance of stirring up additional dust and debris and driving this into smaller crevises still.