Hi, just got a Sigma 10-20mm f3.5 and I'm doing calibration for my Nikon D90 + NN5 + RD8.

What I can't figure out is how may rows to shoot.
There are no full spherical pano calculators out there

I'll try a 2 row + nadir + zenith, see how it goes.
Upper row: +30 pitch 5 steps (72 deg)
Lower row: -15 pitch 5 steps (72 deg)

It should get me covered but there could be a better arrangement.
Any suggestions?