I am in the middle of writing a paper that involves, among other things, a step that uses Richardson-Lucy deconvolution on a 1D array. I know how Richardson-Lucy works as there is quite a lot of published information on it. However, the preconditioned option in Mathematica seems to do a better job, but I have absolutely no idea what it is doing exactly. If I don't know what it does I can't write about it because it is a black box. Does anyone know what the preconditioned option does exactly? I am using Version 10 of Mathematica.