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Up: Optical colour maps

2. Observations

CCD images through broad band B, V, R and I filters were obtained of the nine galaxies, using a thick-coated, frontside illuminated blue-sensitive Tektronix (tex2html_wrap_inline2617) CCD camera located at the Cassegrain focus of the 2.5 m Nordic Optical Telescope (NOT) on La Palma, during the nights of 12 and 14 November 1990 (NGC 1068, NGC 3227, NGC 4151 and NGC 7469) and 25 and 26 December 1992 (Mrk 3, Mrk 78, Mrk 348, Mrk 573 and NGC 1667). The pixel scale employed in each case was 0.20'' pxtex2html_wrap_inline2621. Conditions were photometric on 14 November 1990 and 25 December 1992, with generally subarcsec seeing. On 12 November 1990 and 26 December 1992, conditions were poorer with seeing 1.0 - 2.3''.

Table 1 gives details of the observations for each galaxy; it is formatted as follows: Column (1): the name of the galaxy; (2): the date of the observation; (3): the filter used, (4): integration time and (5): seeing during the observation. Field stars were present in the frames of NGC 7469, Mrk 3, Mrk 348, Mrk 573 and NGC 1667. For the other galaxies, seeing estimates were based on images of standard stars taken close in time before or after the galaxy observation.

Table 1: Journal of the observations

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