How Many Images Should I Stack for Noise Reduction (in Starry Landscape Stacker or Sequator)?

With programs like Starry Landscape Stacker or Sequator image stacking for noise reduction has become very easy to do. The main question then is how many images should I stack? This question can actually be answered analytically with math and statistics but I&rsquo;m not going to go into the details except for the final result. If you want to learn about the derivation, I suggest you look at the…