BVRI measurements were carried out at Calar Alto (Almeria, Spain) during
May and July 1993 (when the seeing was poor) and August 1995 (when the seeing
was good) using the 1.23 m telescope of the Centro Astronómico
Hispano-Alemán (C.A.H.A.). The telescope was equipped with a
pixel
TEK 6 CCD camera. The CCD detector is built into a Dewar filled with
liquid nitrogen and was cooled to
. The pixel size is 24
which is
equivalent to 
. The following Johnson filters were used
The instrumental magnitudes were corrected for atmospheric extinction and
transformed to the BVRI Johnson system by means of standard stars from
the fields
The standard stars were chosen from the lists of Landoldt (1992),
Christian et al.
(1985) and Odewahn et al. (1992). The standard star observations were made at
different air masses at least three times per night. The reductions were carried out
with ESO-MIDAS 95 software. After flat field and dark field corrections, the fluxes
of the single stars were computed using a single aperture routine which subtracts
the effect of the sky background in the vicinity of each star.
All stars were observed on at least two occasions and exposure times for the field
stars ranged from 1800 s to 900 s in B and from 1200 s to 700 s in V whereas the
corresponding exposure times for R and I were 400 s. For the standard stars
the exposure times were 300 s in B and V and 100 s for R and I. The
processing and conversion of the field and standard raw instrumental
magnitudes to magnitudes relating to the Johnson system was carried out
producing magnitudes which are correct to at least 
mag.
| Field | Object | RA | Dec |
| 1 | LDN544, B127 | 19 01 33 | -05 26 47 |
| 2 | LDN549 | 19 02 10 | -05 15 37 |
| 3 | LDN567, B132 | 19 04 11 | -04 25 29 |
| 4 | LDN543, B134 | 19 06 55 | -06 14 19 |
| 5 | LDN1113, B367 | 21 44 18 | 57 10 57 |
| 6 | LDN1031 | 21 45 54 | 47 13 53 |
| 7 | LDN1225 | 23 12 16 | 61 39 59 |
| 8 | LDN1252 (a,b,2) | 23 46 01 | 63 18 42 |
| 9 | LDN1257 | 23 56 10 | 59 49 50 |