How did VLT's adaptive optics obtain this resolution for Neptune? Is it really working in visible wavelengths? This image of Neptune taken with the VLT is really impressive. The resolution is achieved by recent improvements in the adaptive optics.


Gizmodo: New Super-Crisp Images of Neptune Show How Far Our Telescopes Have Come
Space.com Telescope Upgrade Produces Stunningly Clear Views of Space


But I don't really understand, is this coming from just one 8 meter mirror, or is this using more than one of the four that make up the VLT? Also, is this really using adaptive optics that work in the visible, including blue wavelengths? Or is this a false-color image? See the excellent answer(s) to Why (actually) aren't ground-based observatories using adaptive optics for visible wavelengths?
It is an image taken with the new narrow field mode of the MUSE instrument using the GALACSI Adaptive optics module on a single (UT4) VLT telescope using laser guide stars.

I am having a great deal of difficulty (e.g. from this press release) in working out at what wavelength(s) this image was taken. I do not believe that the AO system is working at blue wavelengths and therefore the comparison with HST (which certainly does) is somewhat misleading. I think (from ESO's own instrumentation pages) that the MUSE narrow field mode has zero efficiency at blue wavelengths and the description of GALACSI only talks about AO correction approaching diffraction limited images at 650 nm (i.e. red wavelengths).

The captioning to the press release images found here suggest that the shortest wavelengths used in this false-colour image were 550nm and that most of the detail you see is coming from redder wavelengths (600-920nm).