Panorama Pro - Photo Stitcher

I’d like to have an option to correct the panorama distortion that happens after the stitching the pattern of connection always makes a U-pattern with the middle of the landscape shot dipped and the left and right edges upturned and pinched. Some additional treatments to eliminate the banding in the sky are also needed. I lock the exposure and focus of all the individual photos and overlap on the 1/3 lines to assist. Overall very nice app. HDR preservation would also be ideal.