Visual observations

The visual observations for the following guide were carried out by the author during two principal time periods: 1992–2001 and 2006–2010. In 1992, a computer printout of the Herschel catalogue was obtained from David and Brenda Branchett of the Astronomical League. The list had been generated by Father Lucian Kemble to facilitate an ongoing project to observe the entire Herschel catalogue with modern amateur telescopes.

All objects in this guide were located by the starhopping method, whereby the observer uses star charts to proceed from a known location to a new target. The present author’s procedure was to record observations on a preprinted form. In addition to identifying the target, the date and time observed, viewing conditions, location, telescope and magnification used, a written description of the object was included and further supported by a field sketch with surrounding stars placed as accurately as possible. Later, each observation was compared with a Digitized Sky Survey (DSS) image of the object in question. If the star patterns and general appearance of the object matched the DSS image, the object was recorded as seen. In the overwhelming majority of cases, the first attempt was successful. However, there were occasional faint objects or objects located in crowded fields that were not successfully recorded the first time. If the DSS image indicated a negative observation, the procedure was repeated until success was attained.