Because it isn’t really an airship as we know them. We also have no idea of scale in that photo.
I can recall when BAe released this photo in the early 2000s:
This is Raven. I envisaged a massive Typhoon sized aircraft. When I saw it, it had about a 4-5ft wingspan! Maybe that is why there aren’t many photos of it? It also flew at the remote Woomera range, so not many folks there to photograph it either (nor Corax, Kestrel or Demon).