So lets check the truth.
8 cm (3") distance no zoom
that is nearly as close as you can get and the flash did not blow out the white parts, the colors are right on target.
15 cm distance no zoom
10 meter distance 10 x zoom
there is just rudimentary lighting there, will post a non flash to compare later, but 10 meter is a nice distance to even get some usable foto.
Conclusion, the HX5 flash does a nice job in throtteling down or jumping to ISO 800 to cover the maximum distance.
All fotos in IAuto mode.