Table 2: Observational configurations employed in the four different observing runs.

	Run 1	Run 2	Run 3	Run 4
Dates	19-21 Jan. 1998	15-17 Mar. 1999	18-19 Aug. 1999	25-27 Apr. 2001
Telescope	CAHA 3.5 m	WHT 4.2 m	CAHA 3.5 m	WHT 4.2 m
Spectrograph	CTS	ISIS blue	CTS	ISIS blue
Detector	CCD TEK 12	EEV12	CCD TEK 12	EEV12
Dispersion	1.08 Å/pixel	0.80 Å/pixel	1.08 Å/pixel	1.72 Å/pixel
Wavelength range	3570-5770 Å	3700-5269 Å	3570-5770 Å	3700-6151 Å
Spectral resolution	3.6 Å (FWHM)	3.5 Å	3.6 Å	6.56 Å
Slit width	2.1 arcsec	2.0 arcsec	2.1 arcsec	2.0 arcsec
Spatial scale	1.1 arcsec/pixel	0.8 arcsec/pixel	1.1 arc/pixel	0.8 arcsec/pixel