I understand that some astrophotographers use an atmospheric dispersion corrector (ADC) when shooting separate RGB videos with a monochrome camera. In principle, even though the final RGB images get aligned in processing and this automatically takes out the dispersion to a large extent, dispersion varies continuously with wavelength and there must be some dispersion and resultant bluring within each R-G-B image. Hence, there may be sharpening to be had by adjusting for dispersion in each color band. The question I have is how much difference does this make in practice and how do you do it? By trial-and-error until it looks sharper, or is there a tool or a more systematic approach?