Hi, I'm using ArcSoft's panorama maker for this kinda shot for stitching.
he colors are just beautiful. If you've still got the original files, I can show you what's possible.
jeroen, do you use photoshop?.. why not to try selective area and use rotate or distortion tool.. you can handle the inclination of angles at one of them and then try to make pano with photostich..
Tried to merge these images which where not intended for a panorama, used Canon's photostich, but because of the different vertical angles this was the best possible result.