In addition to many diseases and conditions that only affect some people, a few inescapable age-related factors affect all observers vision as we age. These are decreased maximum pupil dilation, low-light sensitivity, and rate of dark adaption. By understanding these problems, older observers can implement observing techniques, behaviours and hygiene measures to minimise the deleterious effects on observing enjoyment.
Supplementary material
For anyone wanting more information about Joe Cali's talk, the link below to Joe's web page has links to a series of short articles covering the material / subject areas in the talk, the slides in PDF format, and an excel spreadsheet for generating light loss tables as equivalent smaller telescope apertures of the type displayed during the talk. All files can be downloaded from Joe's web site at this URL: -
https://joe-cali.com/NACAA/