Left panel – VLT/FORS1 V band co-added image of the Hydra I cluster core with NGC 3311 and NGC 3309 visible in the upper part of the image. A two dimensional (2D) photometric model is fit within the region of limited by the box (see Sect. 4.1 for details). Middle panel – The mask “cmask” adopted for the 2D-model fit of the VLT/FORS1 data, which masks stars and galaxies in the chosen region as well as the centers of NGC 3311 and NGC 3309. Right panel – The mask “allmask” for the 2D fit that also masks part of the north-east regions, in addition to the stars and galaxies in “cmask” (see Sect. 4.1 for details). In the middle and right panels, the two crosses indicate the positions of the centers of the two giant galaxies.