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How to Do Visual and CCD Photometry

  • Martin Mobberley
Chapter
Part of the Astronomers' Observing Guides book series (OBSERVING)

Visual Photometry

Although we are now in the twenty-first century, when many leading amateurs use CCD cameras for photometric measurements, there are still plenty of visual observers who make magnitude estimates using their own eyes and good judgement, with no technical wizardry. Using big Dobsonians, typically of 0.4-m or 0.45-m aperture, or Schmidt–Cassegrains of 0.35-m aperture, they can make estimates down to 16th magnitude. Many Dobsonian users can locate their targets more efficiently than using a motorized Go To system, as they can haul their telescopes around the sky much more quickly than a few degrees per second and without the fear of any gearbox failures (common with heavy out-of-balance fork-mounted Schmidt–Cassegrains). The visual approach also puts the observer in touch with reality in a way that the CCD observer never can be: photons from the outbursting dwarf nova are actually hitting the retina!

Of course, it takes years to gain sufficient experience so that you can,...

Keywords

Magnitude Estimate Full Width Half Maximum Variable Star Comparison Star Light Pollution 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Copyright information

© Springer Science+Business Media, LLC 2009

Authors and Affiliations

  • Martin Mobberley
    • 1
  1. 1.UK

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