Time series in this collection were derived from CCD images obtained at the Kolonica Observatory, Slovakia.

The observations were carried out to monitor selected fields centred on eclipsing binary stars with two small telescopes.

The first instrument, ZIGA (PlaneWave CDK20, Corrected Dall–Kirkham), has a 508 mm aperture and is equipped with a Moravian Instruments G4-16000 CCD camera with UBVRI Bessell photometric filters. The second instrument, Alica (Explore Scientific MN-152, Maksutov–Newton), has a 152 mm aperture and is equipped with a Moravian Instruments G2-8300 CCD camera with Sloan g′ r′ i′ photometric filters. Both telescopes are currently in operation at the observatory.

The time series were produced with a custom photometric pipeline (Parimicha, Š., in preparation). Differential photometry is performed using comparison star magnitudes from APASS DR9.

Beyond the primary target (typically an eclipsing binary), the pipeline derives calibrated magnitudes for all stars in the field with sufficient signal-to-noise ratio. This approach, we believe, may help researchers follow the behaviour of other interesting objects over time.

For each photometric point, we provide the list of comparison stars used in its calculation (which may vary for each star and each image).

The corresponding calibrated images are published separately in the upjs_img image collection.

• Light curves
• Variable stars
• Time domain astronomy