Subject to the individual limitations already summarised, any one of the three methods discussed in this chapter is capable of producing results of publishable accuracy. The first two are of particular interest to those who do not wish to buy special equipment. The ring method, although confined to very wide pairs, is ideal for the beginner who wants to attempt measurement without investing in expensive accessories. The chronometric method is more accurate, can handle closer pairs and is perhaps especially suitable for those who enjoy making their own equipment.
For all other purposes, however, the illuminated reticle eyepiece is superior. In the absence of a filar micrometer or equivalent professional apparatus, the observer intending to embark upon a serious programme of visual measurement, with a view to publishing the results, will undoubtedly find the illuminated reticle eyepiece the most practical option.
1 Courtot, J.-F., 1999, The Webb Society Deep-Sky Observer, 119, 4.
2 Tanguay, R., February 1999, Sky and Telescope, 116.
3 Teague, T., July 2000, Sky and Telescope, 112.
4 Harshaw, R., 2002, The Webb Society Deep-Sky Observer, 128, 1
Jones, K.G. and Argyle, R.W., 1986, Webb Society Deep-Sky
Observer's Handbook, vol. 1: Double Stars, 2nd edition. Martinez, P., 1994, The Observer's Guide to Astronomy, trans. Dunlop, S. chapter 13: Double and multiple stars, Cambridge University Press. Sidgwick, J.B., 1955, The Amateur Astronomer's Handbook, section 18: Micrometers, London.
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