False colour composite images of three gravitational lens systems in our study. The composite images were produced using the HST/ACS WFC and the F555W and F814W filters and NICMOS and the F160W filter for HE0047−1756, HST/WFC3 UVIS channel and the F275W filter and ACS WFC and the F555W and F814W filters for HE 0435−1223, and HST/WFC3 UVIS channel and the F275W filter and WFPC2 and the F555W and F814W filters for HE 1104−1805 (see Table 1 for details). The imaging data were retrieved from the HST data archive (see Section 2.1 for descriptions). For each system, the lensing galaxy is located at the centre of each panel with the horizontal bar in the lower-left corner indicating the 1 arcsec angular scale and the corresponding physical distance at the redshift of the lens. Using absorption spectra of the lensed QSOs, we are able to probe halo gas around the lens on projected distance scales of d ∼ 3–15 kpc across the centre of each lensing galaxy. Note that the lensing galaxy of HE 0047−1756 exhibit consistently red colours as those of HE 0435−1223 and HE 1104−1805 (see Tables 3 and 4). The available F275W images for the fields around HE 0435−1223 and HE 1104−1805 provide strong contraints for a lack of young stars in these lensing galaxies. As a result, the lensing galaxies appear to be red in the composite images that include the F275W band. However, a UV image is not available for the field around HE 0047−1756. Including available optical and NIR images results in the apparent bluer colour of this lensing galaxy.