High‐resolution images of RX J0911.4+0551 are displayed in the left panels with, in the right panels, their corresponding deconvolved versions with improved resolution and sampling. In each band, the individual data frames are deconvolved simultaneously. Top: Stack of three NOT+HIRAC I‐band images. The total exposure time is 900 s. Middle: Stack of nine NTT+SOFI J‐band frames. The total exposure time is 1080 s. Bottom: Stack of 19 NTT+SOFI K‐band images with a total exposure time of 2400 s. For all the three bands, the object is clearly resolved into four QSO images, labeled A1, A2, A3, and B, plus the elongated lensing galaxy. The field of the optical and near IR data are, respectively, 7^{﹩\arcsec﹩} and 9^{﹩\arcsec﹩} on a side. North is to the top, and east to the left in all frames.