At the recent Practical Astronomy Show 2019, Dr. Robin Glover (a physicist and software developer who created the SharpCap program) gave a 50-minute talk about the niceties of long-exposure digital imaging, particularly with modern CMOS microlens sensors:
He explains the differences between CCD and CMOS sensors and the contibutions of noise compared to the background light-pollution levels. He presents very clear explanations of how single-frame-noise varies with exposure length, and how stacking improves the signal-to-noise ratio by the square-root of the number of frames stacked.
Then he combines these factors into an equation to calculate the optimum length of sub-exposures for a given total imaging time.
Unfortunately he runs out of time at the end, and has to hurry through his conclusions.
For those interested in imaging and image processing with DSLR, CCD, webcam or film.
1 post • Page 1 of 1