Fisheye images are unusual in that they produce a very wide-angled but severely distorted image. So is it possible to stitch images of this kind with Autopano?
Well yes, and it is actually just as easy to work with them as with any other kind of image!
A fisheye shot enables wide surface coverage with a minimum number of images.
This makes it very useful for the creation of complete panoramic views for effective virtual tours.
As mentioned above, a virtual tour is based on a panorama, ideally a full spherical panorama.
We will see that to create such a panorama is actually very easy (and can even be done very quickly) using the right equipment:
- A camera
- A fisheye lens
- A tripod
- A panoramic head
Number of necessary shots in function of focal length
It is, of course, possible to create a full spherical panorama (360°x180°) with other lens types.
However, the number of shots required then varies as follows (without counting the shooting time and the risk of stitching process error):
- With a 35mm lens, 52 shots (4 lines of about 12/15 shots) are needed.
- With a 28mm lens, 32 shots are needed.
- With a fisheye 10.5mm lens, only 8 photos are needed.
Finally, essential for shooting full spherical panorama is the setting of the entrance pupil of the camera/lens pair mounted on a panoramic head.
Actually, this setting prevents parallax, a very annoying problem for image stitching because it is impossible to remove. Here is a link explaining one of the techniques you can use to set the ideal rotation point: Setting the nodal point
With the entrance pupil of the panoramic head is set (accurately), the following lesson will show how to use Autopano to create a full spherical panorama with fisheye images.
The Different Types of Fisheye Image
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Fisheye lenses bring lot of image distortion. For example, a basic grid with parallel horizontal and vertical lines shot with a fisheye lens will produce a sphere shaped deformed grid.