According to Schneider, the 360mm Symmar-S will provide 70 degree coverage at f22; the Rodenstock Apo-Sironar-S gives about 75 degree coverage at f11; except for the 120-SW, Nikon's lens provide for a 60 (f5.6) to 70 (f/22) degree coverage with the 120-SW gives 80 degree coverage at f/8 and 105 degree at F/22. I forget how it goes but you can guesstimate the arc in the sky by pointing one arm directly at the sun and keeping the other at 90 degrees (?) turn in the direction of solar travel.

Thomas