I know I deserve to be laughed off the forum, but to save you all from making the same mistake, here's what I've been doing for almost three hours today!
I noticed my sensor had some serious crud on it, including two tiny curly hairs (no, not that type!) - from clothing, I'm guessing. I could see 30+ specks including about 10 at f/4.5 using my 100-400L!
So it was time to get the ol' Eclipse out and have a dig inside my beloved EOS 30D...
Battery was fully charged, and I had two peck-pad covered sensor-swabs. I took a test shot of the sky, out of focus at f/32 and even on the camera's display, it was like looking down on a load of policemen wandering around inside an ice-cube, so I trickled two drops of Eclipse onto the swab and....first swipe seemed ok - no residue. Looked through the viewfinder and blow me down, the crud was still there, and a particularly large blob seemed to have shifted from top-right to bottom-left!
Two more swabs later, and again, through the viewfinder - BLOBS!!!!!!
Ah. No more sensor-swabs! So, I jumped in my car and drove about 14km (round-trip) to the photo shop to get some more wipes.
Back to scrubbing and THREE MORE SWIPES LATER.......CRUD ALERT!!!!!
Then, as the sweat began to build, I thought to myself....."top-right to bottom-left"...."through the viewfinder"...............
What had I done wrong? Not bothered to check the images each time I took a post-clean test shot....just looking through the viewfinder at the same blob.
What was I really looking at? A speck of dust.....on the bottom of the pentaprism.
So, one careful "up-swipe" above the mirror (not on the sensor at all!) and the blob was gone.
Please....don't be a daft berk like me. If you do your own sensor-cleaning, LOOK AT THE PICTURES after each swipe. NOT just through the viewfinder.
And of course, check your pentaprism isn't dirty too!