I really worked pretty hard for this one. It is also from the Smokies this August (on Meg's and my Honeymoon Part II). This is Roaring Fork. It boasts the steepest decent of any stream its size in the Eastern United States. There is a beautiful little one-lane drive along it, and we stopped at this pool to fly fish and photograph. Fly fishing came first of course - don't want to scare the fish :) After no fish, I got in the stream, submerged my tripod (and myself bit), checked to make sure the front element of my lens was not getting totally soaked from the rushing water and clicked away. I am amazed at how steady the images came out with the water rushing on the tripod.
Photo Notes: Light is not always simply influenced by color temperature; it can often take on hues from surrounding objects. In the case of a stream surrounded by a sea of green, the camera will see the scene as having a green hue. A slight move toward magenta in Lightroom brings it back to how our eyes are able to see it. I am ever increasingly impressed with our eyes marvelous ability to render the most difficult of optical scenes with acuity.
One of the keys of success with panoramas is to shoot "on-level" - unless using a tilt-shift lens. In this case level was 6" above the water downstream of what I was photographing. Accounting for the shooting angle allows the resulting panorama to be free of distortion left-to-right.