Although dust in elliptical galaxies is ubiquitous, its origin is not well understood, given the absence of young stellar populations with classical dust producers like post-AGB stars or supernovae. Many authors still promote an “external” origin through galaxy mergers. However, at least in one case, we have shown that the dust has its origin in nuclear dusty outflows (NGC 1316 or Fornax A). This talk presents two more key galaxies: M87, the central galaxy of a Virgo subcluster, and NGC 4696, the central galaxy of the Centaurus galaxy cluster. The discussion is based on HST images and on wide-field and narrow-field MUSE data cubes. In M87, dust filaments emerge from the nucleus and seemingly from jet knots. More dust than found in the literature is present, including a dust filament starting from the tip of the jet. The jet itself is fine-structured down to the HST resolution limit, so its relativistic character is in doubt. NGC 4696 shows similar dust properties. Better visible is here an optical continuum radiation from the dust which directly indicates cooling of a hot ISM in magnetic fields. All evidence support a scenario, where dust forms in situ as the final cooling product of a multi-phase magnetised ISM.