Data were obtained with 18 different telescopes at 15 sites in 12 countries, utilising both CCDs and PMTs. For the CCD observations, care was taken to avoid having the very bright and close-by star $\upsilon$ Ori on the frames by placing V1162 Ori near the edge of the field of view. For PMT observations the disturbing effect of a close (10 $\hbox{$^{\prime\prime}$ }$ ), 3 $.\!\!^{\rm m}$ 1 fainter neighbouring star on the observational noise was minimised by including the star in the aperture. The observations were, with few exceptions, done through the Johnson V filter. The list of participating observers and sites is given in Table 1, where we also give the number of extrema and hours of data collected with each telescope.

The bulk of the data was reduced by the individual observing teams, and several different reduction procedures were therefore applied. It is beyond the scope of the present paper to describe them all, we will just add that the applied procedures follow general and established methods for reduction of CCD and PMT data. Differential magnitudes were, both for the CCD and PMT data, measured with respect to the star GSC 4478-0019, which is slightly brighter and situated only 3 $^\prime$ from V1162 Ori. Times of observations were recorded as mid-exposure and converted to Heliocentric Julian Date.

Table 1: List of sites participating in the campaign. Telescope diameters are given in meters.
Observatory Location Observer (#extrema) Telescope Detector #hours

SAAO S. Africa T. Arentoft (44), L. Freyhammer (30), G. Handler (16) 1.00 CCD 77.0

SAAO S. Africa G. Handler (6) 0.75 PMT 4.9

SAAO S. Africa G. Handler (6) 0.50 PMT 3.1

Athens University Greece P. Niarchos, K. Gazeas, V. Manimanis (26) 0.40 CCD 33.2

Kryonerion Greece P. Niarchos, K. Gazeas, V. Manimanis (17) 1.22 CCD 22.9

LNA Brazil A. Bruch (26) 0.60 CCD 33.5

Xinglong China Z. L. Liu, A. Y. Zhou, B. T. Du (16) 0.85 CCD 18.9

Beersel Hills Belgium P. Van Cauteren (14) 0.40 CCD 20.6

Ege University Turkey C. Akan, C. Ibanoglu, S. Evren, G. Tas (14) 0.48 PMT 25.5

San Pedro Martir Mexico E. Poretti (3) 1.50 CCD 3.8

Merate Italy E. Poretti (7) 0.50 PMT 10.8

Mt. Laguna USA D. W. Dawson (9), D. Johnson (2) 0.50 PMT 14.5

Siding Spring Australia R. R. Shobbrook (5) 0.61 PMT 6.2

Sierra Nevada Spain R. Garrido (4) 0.90 PMT 4.9

Braeside USA R. Fried (4) 0.40 CCD 4.6

ESO Chile C. Sterken (3) 1.54 CCD 4.3

Lick USA C. Blake (1) 1.00 CCD 1.4

Total (253) 290.1

**Table 1:** List of sites participating in the campaign. Telescope diameters are given in meters.
Observatory	Location	Observer (#extrema)	Telescope	Detector	#hours
SAAO	S. Africa	T. Arentoft (44), L. Freyhammer (30), G. Handler (16)	1.00	CCD	77.0
SAAO	S. Africa	G. Handler (6)	0.75	PMT	4.9
SAAO	S. Africa	G. Handler (6)	0.50	PMT	3.1
Athens University	Greece	P. Niarchos, K. Gazeas, V. Manimanis (26)	0.40	CCD	33.2
Kryonerion	Greece	P. Niarchos, K. Gazeas, V. Manimanis (17)	1.22	CCD	22.9
LNA	Brazil	A. Bruch (26)	0.60	CCD	33.5
Xinglong	China	Z. L. Liu, A. Y. Zhou, B. T. Du (16)	0.85	CCD	18.9
Beersel Hills	Belgium	P. Van Cauteren (14)	0.40	CCD	20.6
Ege University	Turkey	C. Akan, C. Ibanoglu, S. Evren, G. Tas (14)	0.48	PMT	25.5
San Pedro Martir	Mexico	E. Poretti (3)	1.50	CCD	3.8
Merate	Italy	E. Poretti (7)	0.50	PMT	10.8
Mt. Laguna	USA	D. W. Dawson (9), D. Johnson (2)	0.50	PMT	14.5
Siding Spring	Australia	R. R. Shobbrook (5)	0.61	PMT	6.2
Sierra Nevada	Spain	R. Garrido (4)	0.90	PMT	4.9
Braeside	USA	R. Fried (4)	0.40	CCD	4.6
ESO	Chile	C. Sterken (3)	1.54	CCD	4.3
Lick	USA	C. Blake (1)	1.00	CCD	1.4
Total		(253)			290.1

Using BV photometry obtained at SAAO and by photometry obtained at ESO (PaperI), we determined the relative colours of V1162 Ori, the comparison star and a check star, GSC 4778-0025, which will be used to investigate the stability of the comparison star. The V, B-V values for V1162 Ori were fixed to those of Poretti et al. (1990, V=9.89, B-V=0.31), and b-y to that of Hintz et al. (1998, b-y=0.187). We found that the comparison star, GSC 4778-0019 (V=9.73, B-V=1.55, b-y=0.91) is very red, and differs significantly in colour from V1162 Ori. The check star, GSC 4778-0025 (V=12.58, B-V=0.80, b-y=0.47), is somewhat fainter than V1162 Ori and the comparison star.

Photometric light curves of very different length and quality were collected at the many sites during the campaign. As noted above, some light curves cover only single maxima or minima, while others cover several hours and cycles. The observations were not coordinated, but in a few cases did observations overlap, unfortunately only shortly and in poor weather at one or both sites. In Fig. 1 we show examples of overlapping data from two nights during which the weather was non-photometric at one of the two sites. The agreement between the overlapping data is fairly good. We show the difference between the data from the two sites (triangles); the scatter is high in the first night (7.4 mmag rms) and at a more acceptable level during the second night (4.8 mmag rms). In the left-hand panel there is also a systematic trend present in the difference. Such trends can be due to differences in filter passbands or, because the comparison star is very red, extinction. Our best PMT data have rms-scatter within a night of just below 2 mmag, whereas our best CCD data have rms scatter of about 2.5 mmag.

2 The data