I used to be an astronomer back in the 90s. The technique we used was take 5 pictures, deliberately moving the telescope between exposures to make a mostly-overlapping grid. Then a simple median of the 5 images (once aligned) canceled out hot pixels or dead pixels in the chips — these were cutting-edge 4K x 2K chips at the time and often had imperfections. I like the “lucky image” concept, which makes a lot of sense in the context of variable focus or shake. I had not heard of that technique before.
Originally shared by Robert Love
Interesting blog post on high dynamic range (HDR) computation in Android’s Camera app.