Little planet photograph are looking very cool and offer an effect where a photo (typically a panorama) is modified in a way that it looks like a planet.
The major steps to create a little planet photo are:
- Make your image a square image
- Turn your photo upside down
- Transform your photo to polar coordinates
Over here I want to use an artificial photo to show exactly how the original image is transferred. Therefore you can take the photo already in a format fitting for your specific little planet.
This is the original image:
I am using a raster that you better see what part of the image is transferred where to.
In every corner of the original photo there is a different color to see where this corner can be found in the final image.
Additional there are some colors at the ground (green) and at the sky (blue).
The red curve has a special meaning we will see soon.
After you did all transformations for the little planet you will get this image (planet):
Ground: In our final image you can see that the ground is now in the center of the planet and is heavily transformed. It is shrinked quite a lot and therefore you should not have too much detail in the bottom part of your image.
Sky: You can see that the sky is around the whole planet and is stretched quite a bit.
Stiching: The left part of the image is now glued to the right part so you have to make sure that both sides of the image are aligned – typically no problem with 360° panoramas.
Square: The red curve we have in our original image is now a perfect rectangle. This is useful if you want to crop your final image within your planet. Using the red curve in the original image shows you clearly what parts will be lost.
Stretching/Tightening: If you want to make sure that the middle part of your photo (horizon) stays the same length in the final photo you can use a photo ratio of π. Just make a short calculation and you will see why ;)
In this example we have an aspect ratio of 3:1 which is pretty close to it. This is very useful if you want to make sure the the middle part of your photo is not distorted that much.