Dust spots occur in many images. Some of them are easy to see and fix, but others seem to elude me. I’m getting better at noticing them but I still need some help and that’s where Adobe Lightroom 5 comes to the rescue.
In Develop mode, select the spot healing tool and you’ll see below your image there is an option to “visualise spots”. This will turn your image into a black/white contrast outline, highlighting the dust spots so you can fix them. You can switch between this view and the standard view of your image by toggling the Visualise Spots checkbox. This will help you ensure the spot fixes have worked well.
Below are the steps using one of my random images as an example. You can click any of these to view them in higher resolution: