Or a rabbit hole? Down or up?
A hyper-fisheye IR shot of the sky in woodland. The 'hole' is the view of the sky, the surrounding area is the ground. It looks like that because of the very wide field of view. I'm not explaining this very well am I...
The image has a field of view of 349 degrees according to Hugin, the sky is at the centre. The numbers are part of the pano head - I left them in since it makes it more mysterious.
In testing I took this one in my living room earlier. The field of view here is 344 degrees. The carpet features strongly in this picture
I apologize in advance if these mess with your head