With what Fisheye obiective are made this photos?
You can us any lens for that. A fisheye does it with fewer shots - any fisheye. ThatÂ´s the only difference: the amount of shots.
On a FX camera itÂ´s usally 15mm or 16mm fullframe-fisheye or 10,5mm or 8mm circular fisheye.
On a DX camera itÂ´s usually 10,5mm fullframe-fisheye or 8 mm or shorter circular.
But you also can use a non-fisheye - just need to make more shots. The advantage of making more shot with a non-fisheye is
to get higher resolution.
See it here: Canon 5D2, Nikon 35mm lens, 45 shots - http://www.360impressions.de/Klapheck/
use the zoom.
Using the 35mm you get 35000px width which means around 700mpx doing 45 shots.
Using a 15mm fisheye you get 16000px width 120mpx which means around 120mpx doing 6 shots.
That means the fisheye shots donÂ´t provide such a deep zoom-range.
The key to all this is a very precise NPP-alignment - most important for indoor shootings.