I did a few different Polar, and spherical panos. Polar and the spherical panos are different from eachother in a few different ways. First of all, the polar looks like a mini world with the sky on the outside. The sphereical ended up looking somewhat like a snowglobe with the sky on the inside, and the land on the outside. I know that I am not very good at explaining
Polar and spherical panos are created almost exactly alike. The only difference is that with the polar you flip your image first then you polar the coordinates. So the polar ends up looking like a tiny world. The spherical ends up looking like a snow globe.