if you buy PTGuiPro software then you do not have to do anything to the pics at all. simply load the pano images, hdr or regular, and the software makes your pano.
PTGuiPro is the best pano maker out there. expensive, but it does more than any other one. it also makes 360degree and 720degree spherical panos. i do not know of another software that can. it also has seemingly no limit on the number of pics used to make the pano.