Text and pictures © 2006-2023 Guillaume Dargaud
Last updated on 2021/11/05
"When the Light of the Endless was drawn in the form of a straight line in the Void... it was not drawn and extended immediately downwards, indeed it extended slowly — that is to say, at first the Line of Light began to extend and at the very start of its extension in the secret of the Line it was drawn and shaped into a wheel, perfectly circular all around." — Hebrew quote from Umberto Eco's Foucault's Pendulum.
Left: Bird's eye view of the installation of the snowmachine parking power supply by Michel before the end of the 2005 winterover. The original panorama can be seen here. It really shows a 'planet Antarctica' effect.
Right: The same image shown reversed: instead of having the bottom of the panorama moved to the center, you have the top.
I later discovered that this type of image projection is also known as polar panorama.
For an more detailed explanation of what those images are, see the BirdseyeWarp tutorial. The program used is freeware. Let's just say that those images are 360° fisheye images. A normal fisheye lens covers 180°: 90° left, right, up and down. This one extends all the way in the back of the photographer ! The most expensive lens in the world ? Niet, just a little bit of geometric transforms. Those pictures could also be called something pretentious such as 'total circular frame images' or some such.
Left: Bird's eye view taken from below the astronomy platform. My gloves are on the ground and the ceiling of the platform (above the camera) is all around the image circle, 180° away.
Right: The same view, reversed. Note that now it's the gloves which are all around the image.
Right: Same effect indoors. Not quite the same...
How does this work in practice ? I first take a bunch of images from a tripod (nodal point rotation, blah, blah, blah), preferably with a fisheye lens, and build a panoramic image with the adequate software (I currently recommend PTgui). Once I have a 360:180 panorama, I just load it into my little program and get those... things. Whether they are truly artistic or just a display of clever mathematics is left as an exercise to the reader.
On the images above, I let the corners be black or set them to a transparent value. Here I cropped the image somewhat and colored the corners to some neutral value taken from the edge of the image circle.
Left: This one is technically a reversed fisheye image. I took a single fisheye image with the camera on the ground, pointing at the zenith. I then unrolled it into a 360x90° panorama with FisheyeWarp and finally imported that panorama into BirdseyeWarp for the reverse process. Note that if you select the [Bottom -> Center] option, you get back the original image.
Right: Similar to the first image above, the towers are a bit too dilated for my taste, almost as bad as a dumbbell.
Left: Fortress on 'Planet Briançon'
Right: Image taken from the walls of the old town of Briançon.
Left: Another image taken from the top of the fortress walls. Here's the original panorama.
Right: Effect reversed to show the closing roofs in the narrow streets of the old city. As seen from the eye of a rat looking through the ground sewers. Hmmm, rat's eye, now here's an idea for a software name !