Light microscopy and adaptive optics, my uncensored and biased opinions

If you are new to adaptive optics (AO) like me, the selection of right hardware can be daunting. Starting with a  wavefront sensor - they range in price, resolution, and many options which are not obvious. By practical trial and error I learned something about resolution, which wasn't obvious to me a year ago. The Shack-Hartmann wavefront sensor (WFS) is essentially a camera with a lenslet array instead of an objective.  There are sensors with 15x15 lenses, 30x30 and higher. Naively, you might think "the more the better" - we are digital age kids used to get high-res for cheap. However, there is a catch. High-res sensor, say, 30x30 lenslets, divides your photon count by 900 per spot. Roughly speaking, when you image a fluorescent bead (or another point source) by a camera with "normal lens" (not a lenslet array), and your peak intensity is 2000, this makes a very nice, high SNR bead image. However, is you switch to Fourier (pupil) plane and image the wave...

Shack-Hartmann wavefront sensor is a brainchild of Cold War, born in late 1960-s by the need of US Air Force "to improve the images of satellites taken from earth"  -guess who's satellites caused such intense interest of Uncle Sam. The working principle is simple and elegant - the wavefront sampled by an array of micro-lenses, and its local slope is converted into displacements of focal spots: To make an SH sensor today, one needs an array of microlenses and a digital camera. The main difficulty is accurate calibration and the software which will convert camera images into wavefront reading. Thorlabs sells reasonably priced SH sensors and I purchased the WFS-150-7AR for my project. The good It is well built, comes with plate adapter and a C-mount ring adapter. The software runs smoothly and produces expected results (flat wavefront) when tested on spatially filtered and collimated HeNe laser. The manual is very detailed, and API comes in C, C#, and LabVie...