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aims: We present VRi photometric observations of the quadruply imaged quasarHE 0435-1223, carried out with the Danish 1.54m telescope at the La SillaObservatory. Our aim was to monitor and study the magnitudes and colors of eachlensed component as a function of time. methods: We monitored the object duringtwo seasons (2008 and 2009) in the VRi spectral bands, and reduced the datawith two independent techniques: difference imaging and PSF (Point SpreadFunction) fitting.results: Between these two seasons, our results show anevident decrease in flux by ~0.2-0.4 magnitudes of the four lensed componentsin the three filters. We also found a significant increase (~0.05-0.015) intheir V-R and R-i color indices. conclusions: These flux and color variationsare very likely caused by intrinsic variations of the quasar between theobserved epochs. Microlensing effects probably also affect the brightest "A"lensed component.

I. Flux and color variations of the quadruply imaged quasar HE 0435-1223