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VW CrB has been discovered as the SU-type dwarf nova by S.Antipin (IBVS 4343). T.Kato [vsnet-campaign-dn 3876] informed on the "VW CrB likely superoutburst". The star has been observed from HJD 2452847.4557-.4956 using the 38cm telescope of the Crimean Astrophysical Observatory equipped with the SB ST-7 CCD camera with the R filter. The comparison star GSC 2576.2027 (same as that used by R.Novak, IBVS 4489 (1997)) has been used. The light curve exhibits a superhump-like variability. The brightness estimates during 54% of the superhump period estimated by R.Novak varied from Var-comp=1.6 to 2.1 with a mean value of 1.85 mag. However, at maximum, which was missed because of weather conditions, the magnitude may be slightly brighter (extrapolated estimated values are 1.5-1.6 mag using the shape of the curve obtained by R.Novak). The moment of minimum is HJD 2452847.468+/-0.002 (Var-Comp)=1.98+/-0.03 The mean value <Var-Comp> is by ~0.4 mag fainter than that obtained by R.Novak. However, it is not clear, whether this is the result of real brightness difference during different nights, or the result of difference of the instrumental systems. The check star (R.A.=16h 00 19, Dec=+33 08'48", "c" at the map by S.Antipin) is fainter than the comparison by 0.045 mag in R, whereas the VSNET V chart ( http://vsnet.kusastro.kyoto-u.ac.jp/vsnet/DNe/vwcrb9705.html ) gives V=14.08 and 13.14 for the check star and the comparison star, respectively. This argues that the check star is very red and should not be used as one of the comparison stars. The brightness difference at the charts presented as the links from http://vsnet.kusastro.kyoto-u.ac.jp/vsnet/DNe/var21crb.html also varies from one instrumental system to another. Assuming the brightness of the comparison star to be 12.95 ( http://vsnet.kusastro.kyoto-u.ac.jp/vsnet/ftpfile/DNe/var21crb/crbvar21.gif) one may roughly estimate the mean brightness of the variable to be ~14.8 mag. A.V.Baklanov (alex-baklanov@mail.ru) I.L.Andronov (il-a@mail.ru) E.P.Pavlenko (pavlenko@crao.crimea.ua) Department of Astronomy, Odessa National University Crimena Astrophysical Observatory
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