I took this photo in order to compare the RX100M2 and the HX90V.  (It’s not worth looking at the HX90V result.)

I used the following exposure parameters: ISO 160, f/5.6, 15 sec.  I chose these to more closely match the HX90V which is more limited in available apertures.  I think the results might be better still had a chosen to use a somewhat wider aperture.  This is the RAW file processed in Lightroom only.  (I didn’t see any point in going to Photoshop for this one.)