The lists of available calibration fields and stars are given here forvarious FORS setups, i.e. for Stetson Fields for standard filters,Landolt Fields for other broadband filters, Spectroscopy,empty Fields for Twilight Flats and Polarimetry. Thename of the Observation Blocks already prepared by PSO and available forany visiting observer is given, as well as some information on the fieldor star.

Photometric Standard Stars: Stetson Fields

Template name	Star field	Center coordinates Ra, Dec
Photom-std-NGC121	NGC121	00:28:07.8, -71:13:03.3
Photom-std-T_Phe	T_Phe	00:30:12.1, -46:29:08.7
Photom-std-L92	L92	00:55:09.7, +00:42:49.9
Photom-std-PG0231	PG0231	02:33:40.9, +05:19:15.0
Photom-std-L95	L95	03:53:38.7, +00:07:16.7
Photom-std-E2	E2	04:02:40.0, -44:46:27.22
Photom-std-E3	E3	06:43:13.6, -45:13:28.8
Photom-std-NGC2298	NGC2298	06:48:37.2, -35:58:34.6
Photom-std-L98	L98	06:52:09.3, -00:19:00.31
Photom-std-Ru149	Ru149	07:24:16.8, -00:32:20.1
Photom-std-Ru152	Ru152	07:29:56.5, -02:05:42.13
Photom-std-NGC2420	NGC2420	07:38:28.3, +21:34:02.9
Photom-std-NGC2437	NGC2437	07:41:41.0, -14:50:45.8
Photom-std-NGC2682	NGC2682	08:51:26.2, +11:48:57.3
Photom-std-NGC2818	NGC2818	09:16:23.0, -36:35:20.3
Photom-std-PG0918	PG0918	09:21:37.1, +02:27:16.7
Photom-std-E4	E4	09:23:42.5, -45:24:43.0
Photom-std-L101	L101	09:56:53.0, -00:19:53.7
Photom-std-LeoI	LeoI	10:08:55.1, +12:22:37.6
Photom-std-PG1047	PG1047	10:50:05.3, -00:00:57.4
Photom-std-Pal4	Pal4	11:29:15.5, +28:58:12.4
Photom-std-E5	E5	12:05:13.3, -45:33:56.5
Photom-std-L104	L104	12:42:17.2, -00:31:51.6
Photom-std-PG1323	PG1323	13:25:45.0, -08:49:59.3
Photom-std-PG1525	PG1525	15:28:11.0, -07:14:34.2
Photom-std-L107	L107	15:39:39.6, -00:14:13.8
Photom-std-PG1633	PG1633	16:35:12.1, +09:50:59.0
Photom-std-PG1657	PG1657	16:59:35.5, +07:32:31.0
Photom-std-E7	E7	17:27:20.1, -45:02:28.1
Photom-std-L110	L110	18:42:50.1, +00:08:04.9
Photom-std-NGC6940	NGC6940	20:34:32.0, +28:15:10.0
Photom-std-L112	L112	20:42:27.7, +00:08:46.8
Photom-std-MarkA	MarkA	20:43:59.0, -10:47:01.0
Photom-std-NGC7006	NGC7006	21:01:11.5, +16:12:26.7
Photom-std-PG2213	PG2213	22:16:19.1, -00:21:14.1

Notes: (1) Reference: Stetson, P.B., 2000, Homogeneous Photometry for Star Clusters and Resolved Galaxies. II. Photometric Standard Stars (2000 PASP..112..925S),(2) The links provide Postscript charts of the areas with SR and HR fields indicated, (3) Coordinates are J2000.

Photometric Standard Stars: Landolt Fields

Notes: (1) Reference: Bessel et al. 1979, UBVRI Photometry (1979 PASP...91..589B) and Landolt 1992,(2) The links provide Postscript charts of the areas with SR and HR fields indicated, (3) Coordinates are J2000.

Spectroscopic Standard Stars - and Imaging Standards for Gunn & interference filters

Notes: (*)These stars only have model data above 3200Å, (1) The OB exist in MOS setup and in LSS, using the largest 2.5 arcsec slit -then the OB namecontains "lss-" at the beginning, (2) The links provide detailed information on individual stars, (3) There is also a general description as well as an RA ordered list and an RA-Dec skymap for standards including the above listed, (4) Coordinates are J2000.

Empty Fields for Twilight Flats

Notes: (1) Filters defined in the OB are UBIVR for the evening dusk. For the morning the OB are named ..-RVIBU-.. instead, (2) The links call6.8'x6.8' images from the DSS1 database, (3) Coordinates are B1950.

Highly Polarized Standard Stars for Imaging Polarimetry (IPOL) OT QUEUE: Polar Std IPOL

Readout mode: 200kHz,2x2,low. There are 4 exposures with the retarder waveplate at 0, 22.5, 45, and 67.5 deg.
Please check that the CCD is well exposed (> 10000 counts each exposure) but not saturated! You may need to adjust the exposure time.
Additional information on (some of) these stars are given on the FORS polarimetry page
Finding charts are obtained from 6.8' x 6.8' images from the DSS2 (red) database.

Highly Polarized Standard Stars for Spectropolarimetry (PMOS) OT QUEUE: Polar Std PMOS

Readout mode: 100kHz,2x2,highThere are 4 exposures with the retarder waveplate at 0, 22.5, 45,and 67.5 deg.
Please check that the CCD is well exposed (> 10000 counts each exposure) but not saturated!You may need to adjust the exposure time.
Additional information on (some of) these stars are given on the FORS polarimetry page
Finding charts are obtained from 6.8'x6.8' images from the DSS2 (red)as database.

Unpolarized Standard Stars for Imaging Polarimetry OT QUEUE: Polar Std IPOL

CCD readout mode: 100kHz,2x2,high. There are 4 exposures with the retarderwaveplate at 0, 22.5, 45, and 67.5 deg.
Please check that the CCD is well exposed(> 10000 counts each exposure) but not saturated!You may need to adjust the exposure time.
Finding charts are obtained from 6.8'x6.8' images from the DSS2 (red) database.

Unpolarized Standard Stars for Spectropolarimetry OT QUEUE: Polar Std PMOS

CCD readout mode: 100kHz,2x2,high. We have 4 exposures with the retarder waveplate at 0, 22.5, 45, and 67.5 deg.
Please check that the CCD is well exposed (> 10000 counts each exposure) but not saturated!You may need to adjust the exposure time.
Finding charts are obtained from 6.8'x6.8' images from the DSS2 (red) database.