I cleaned my sensor for the first time using Lightroom. I photographed a white surface at f/22 and imported it into Lightroom. I used the Spot Removal tool with Visualize spots checked as a way of visualizing the dust spots on the sensor.
My first inspection revealed many large and irregular spots with the slider at 50%. I used a blower, and repeated the inspection. I saw fewer spots, but but some needed more work, so I used sensor cleaner and inspected again. This time there were no spots with the slider at 50%. I kept moving the slider to the right until it got to 100%. At 100%, new spots appeared, but they looked different from the spots I had been seeing at lower magnification. These were all pretty much identical in shape and size. They look like tiny squares. I'm wondering if these are not dust spots at all, but rather faulty sensor sites, or maybe just noise.
How far does the slider need to go to find real dust, and how far is too far?