I was taking some pictures at f/14 and can clearly see some bunny spots in the blue sky. That was annoying, so I had to look at the sensor. It was dirty alright and for some reason, the bunnies were concentrating in the far right of the sensor as you can see here. They were visible with the naked eyes. I did not need to use the SensorKlear Loupe I purchased from the photo show a couple of years ago--btw, I highly recommend this loupe if you are doing any cleaning with your sensor.
Blowing air did nothing to remove the bunnies. They were bonded to the sensor. I did not try to Artic Butterfly and instead went straight to wet cleaning. That's when things went kinda downhill.
On the first pass, the Pec Pad removed most of the bunnies but at the same time left streaks on the sensor. The VisibleDust cleaning solution left residues behind as it dried. The streaks were all over the sensor and even without the SensorKlear Loupe, I was able to see the streaks very clearly with my naked eyes. So, I grabbed another Pec Pad and cleaned the sensor once more. Again, streaks all over. I tried yet once more. Same results. I knew it was not dust but residues from the solution. Does the solution have an expiry date? Maybe the alcohol has evaporated? I really don't know but I must have tried cleaning the sensor five more times before I could get a clear sensor.
BTW, my sensor has this halo ring in the lower left corner. It looks permanent to me as I see it in the other shots I took a couple of years ago. Darn it.