Group SL2S J08544-0121 at z_spec = 0.353. Upper Left: composite CFHTLS gri colour image (1 arcmin² = 297 × 297 kpc²). Upper Right: composite HST/ACS F814W-F606W-F475W colour image (24″ × 24″ = 118 × 118 kpc²). We show the proposed multiple-image identification. The dwarf galaxy and the main extra image it produces is labelled. Lower: CFHTLS i band (10′ × 10′ = 2969 × 2969 kpc²). Luminosity isodensity contours of 10⁵, 3 × 10⁵, 10⁶, 3 × 10⁶ and 10⁷ L_⊙ kpc^-2 are drawn (continuous black line), and the white cross shows the location of the SL system.