Optical V-band imaging of 3C 305. Left+middle: the various plots show the same image of 3C 305, but with different intensity-scaling and zooming. On the left is shown the larger environment of 3C 305, with overlaid in blue the contours of HI 21 cm emission (levels: 0.03, 0.09, 0.15, 0.21, 0.28, 0.33 Jy bm^-1× km s^-1). The dashed blue circle shows the region where the H i absorption dominates (see Morganti et al. 2005a). Even though this H i absorption is spatially unresolved, it is strong enough to dominate over any potential H i emission beyond the FWHM of the synthesized beam (dashed black circle on the bottom-left). Right: position-velocity plot of the H i emission (blue contours) and absorption (black contours) along the axis shown in the left plot. Contour levels are at −3, −2, 2, 3, 4, 5, 6 ×σ, with σ = 0.36 mJy beam^-1.