Kuula supports not only 360x180 photos, but also partial panoramas. Partial panoramas are images that do not extend all the way to the top and bottom of the spherical view. Partial panoramas can be captured with some cameras, with mobile phones, but they occur most often in drone photography where the top of the photo (the sky) is missing.
Spherical vs partial vs flat
Kuula uses a proprietary algorithm to recognize what kind of image you are uploading.
The basic rule is: if the image width is larger than 4000 pixels and the aspect ratio is 2 or above, it will be considered spherical. Otherwise the system will assume it's a regular (flat) image.
Panoramas that have an aspect ratio above 2 are assumed to be partial. An aspect ratio above 2 means the width of the image is more than 2 times the height.
After you upload a partial panorama, you may need to adjust the horizon level of the photo for it to look good.
Partial drone panoramas are typically aligned to the bottom - i.e. they cover the bottom hemisphere but not the top part (sky).
Other partials, for example one made with mobile phones or with DSLR cameras, will typically cover the middle section of the sphere, leaving the nadir and zenith empty.
Kuula might not correctly guess which parts are missing. If your image has a bent horizon line, like on the image below, this might be caused by the wrong alignment of the partial panorama.
You can adjust this with the Vertical alignment slider in the editor:
Sky and ground color
One more nice feature is that Kuula will automatically extract a matching sky and ground color to fill in the empty space. No more black holes, instead you will see a patch of solid color smoothly overlayed on the missing parts.
For drone photographers: in order to make the best use of this feature, try to remove the black stripe that some stitching software leaves on the top part of photos, like this one below. Either crop the photo from the top or fill this area with the clone stamp tool in Photoshop.