Astron. Astrophys. 335, 277-280 (1998)

2. Observations

Several images with the central part of NGC 650 centred on the PC1 ("Planetary Camera") chip of the WFPC2 camera aboard HST were obtained on August 5, 1995. Two images (U2SA0203T and U2SA0204T), with exposure times of 80 and 160, were made through the F555W filter, which closely resembles the Johnson-V band. Additional exposures (U2SA0201T and U2SA0202T) were made with the F814W filter. Exposure times were 300 and 500, respectively. All images are "well exposed" with a typical DN1200 (out of DN4096; gain 15 /DN; T = -88C). Both filters adopted are extremely well characterised (Burrows, 1995; Holtzman et al. 1995), and we extract information on zero-points and colour transformations from those publications.

© European Southern Observatory (ESO) 1998

Online publication: June 12, 1998

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