Dust in the lens

[NZMXr]

Canons have a self cleaning function which seems to work reasonably well ... sometimes I have to do a couple of passes but had taken well over 10,000 images before I had any dust issues

[graciousness]

I've had the stupid experience of getting dusts in my lenses (18-55 kit and 70-300 IS) when I was in San Fran 3 years ago. It was a very windy day by the bridge and I stupidly kept changing lens to take photos. Didn't know I shouldn't do that. When I saw that all my photos had dusts, I quickly looked in my sensors and the lenses and lo and behold, there they are IN the lenses.

I did a lot of reading and apparently, Canon lenses (non L's) have a tendency to attract dusts. Expensive to get cleaned and not worth it.

Three years later, though, I've noticed that the dusts have moved in the lenses (on the 70-300 anyway). So you may get lucky.

If you were at the beach, then it wouldn't have been difficult to get the dust in those lenses.

Just upgrade, I say. Maybe the photography gods are telling you something