Explanation about dome remapping

[cfoch]

Hello. Could you please explain why if I apply remap to the rect picture, I get a fully circular dome, that can be used as a texture in a hemisphere 3D object:

./envremap -i rect -o dome etc/rect.tif out/out3.tif

However, if I remap the fisheye (hemi) to dome, I get half of circule projection:

Could you please explain how can I remap a fisheye 180 degrees picture to a dome image? So I can apply it as a texture to a 3D object:

[rlk]

Quite simply, a planetarium dome is expected to depict the sky above you, while a fisheye lens is expected to depict the scene in front of you. So, if you projected that half image onto a planetarium, you would indeed see that group of people in front of you.

You should be able to simply use fisheye and dome images interchangeably without converting between them. If I recall correctly, they're the same, except for their implied orientation.