We present $VR$ magnification ratios of the double quasar Q0957+561AB, which are inferred from frames taken with the 2.56m Nordic Optical Telescope. From two different photometric techniques ($pho2comC$ and $psfphot$) and a reasonable range for the time delay in the system (415–430 days), we find optical continuum ratios depending on the wavelength. These chromatic ratios are consistent with either differential extinction in a dust system or gravitational microlensing in the deflector. Although the dusty scenario is only viable for a compact dust cloud in the line of sight to the A component, the possible values for the differential extinction and the ratio of total to selective extinction in the $V$ band are surprisingly reasonable. To decide on the true origin of the anomalous ratios (extinction, microlensing or a mixed scenario), we are carrying out new monitoring campaigns and planning detailed observations from the best ground–based and space telescopes.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html