I've revisited a few panoramas, this time with a little more care, and using ON1 Raw. The Post Processing is done in two parts:

 

1/ Getting the base images ok, sharpening, white balance, exposure. the aim is to get an image ready for stitching. Apart form everything else, getting the exposure matching is most important in a "flat" scene like this - otherwise you can see the variation in exposure between stitched images (even after PTGui blends them ...).

 

To separate tone of the water and clouds, I applied different white balances using the masking and local adjustments of ON1 Raw - I'm happy how that worked. And some Black and White (20%) to the clouds to clean up any remaining colour cast.

 

2/ After the image is stitched its possible to apply some final post processing; in this case mostly masking, dodging and some vignetting to adjust the overall feel of the image.

 

 

 

 

Its a lot of work, particularly matching the exposure. The camera was in "M" mode and what I learn from this is that for scenes like this (left side was more than 1 stop brighter than the right side) its better to lock the Aperture and ISO and then let the shutter speed float so that each shot gets consistent exposure.

And this was the other image that was reworked. In this case, not much PP at all, other than a few hours fiddling around with getting even exposure between the 12!!! shots which make the panorama. Its a rather impractical 4:1 aspect ratio ...