You shall first need to get four square rectilinear photos.
These four images should have been shot in the four directions given by the normal to a (regular) tetrahedron faces. An illustration of the coverage is shown on this image (click to enlarge)
This web site would complete your information about the tetrahedron...
As an example, this is one way to proceed:
Put your camera on a tripod that is equipped with a spherical panohead. The lens should then be adjusted for shooting at 19.52 degrees of upward inclination and you then take three photos equally angular spaced one from the others.
A Nadir shot shall complete the required set of four images. Just make sure that they have more than about 140 degrees HFOV (*).
What about Stitcher from Realviz?
As this software does not support fisheye lenses, four is the minimum number of (rectilinear) photos that Stitcher 4 will require. This is due to the "limited" FOV of any of such a lens: much less than 180 degrees.
The adequate settings "file/properties" and the four assembled images are shown in workspace of Stitcher 4, on this screenshot:
Another screen shot from a further verification of the stitching preparation and panorama rendering processes;
And this is the resulting panorama (QTVR 2.1MB)
Sorry, this is a problem without an immediate solution from me: the arbitrary 9M Pixels CCD (or CMOS) sensor that I have here digitally simulated and (virtually) used is a 120mm wide square. The lens is a 21.8 mm wide angle (virtual) model. All these figures were selected in order to work around the limits that Realviz has presetted (some are due to license issues and some may be technical) so that very wide rectilinear lenses are not supported by Stitcher. 10mm is the minimum acceptable focal distance for a 24-36mm sensor for instance.
This lens has to near ideal and almost absolutely without any distortion of all kind...
Well, I don't know where I could find such a dream combo
And I wonder if it could even exist in the future?
Quite frustrating isn't it ?
Michel Thoby 29th of August, 2005