VizieR Online Data Catalog: VRI light curves of four contact binaries (Djurasevic+, 2016)

Photometric observations of selected variables were carried out with the wide Bessell V, R, and I passbands closely matched to the classic Johnson-Cousins system, using the back-illuminated EEV CCD 42-40 camera with 2048*2048 pixels. The pixel size, scale, and total field of view are 13.5μ, 0.305''/pixel, and 10*10arcmin², respectively. The camera is attached to the Newtonian focus (f/4.84) of the 1.88m reflector telescope of the Kottamia Astronomical Observatory (KAO) in Egypt, and kept at a temperature of -125° by liquid nitrogen cooling. Exposure times for J0645 were 60, 20, and 10 s for the V, R, and I passbands, respectively; 150, 80, and 60s for J1558 and UCAC4; and 100, 40, and 20s for J2128.

(2 data files).