Light microscopy and adaptive optics, my uncensored and biased opinions

The era of 1750s was an exciting time in the technology scene of England. Marine navigation of the empire demanded better time keeping and ever more precise celestial observation. Educated public was keenly interested in astronomy, partly from beliefs (still strong in our time) that celestial bodies determine our fate, partly from genuine desire to understand the Universe. Fortunes were made in manufacturing watches, navigation instruments, and telescopes. Although refractive (lens-based) telescopes were already well known at that time, they suffered from chromatic aberrations, because of light dispersion in glass: light with different wavelength (color) propagates with different speed and thus gets focused at different distances from the lens, which creates colored fringes in the image. It was widely believed, due to Sir Isaac Newton's works, that chromatic aberration cannot be corrected with lenses. However, some scientists kept pursuing this lead, including Leonhard Euler, who...

In everyday life and in the lab, there is often a mundane but important problem: cleaning optics . It can be your glasses, microscope objectives, AR-coated lenses, or microscopy coverlips. There are many comprehensive online resources on the topic, such as Newport  tutorial  and Photonics review . In practice, I found that achieving clean surface of glasses, lenses, and coverslips is really hard when using recommended organic solvents. I tried chemically pure 99.98% ethanol, isopropanol, acetone, with and without sonication, gentle wiping with special lens tissue pads  from Thorlabs and generic lens tissue. Almost always there is some residual dirt, smudges or dust. Out of desperation, I tried ordinary soap from lab dispenser - applied, gently wiped, rinsed with distilled water, dried with optical tissue. THIS THING DOES MAGIC. The cheapest and most effective way of cleaning optics ever. This became my only way of cleaning glasses, lenses with AR coati...