I did a lot of reading on the internet on that topic and there are heaps of info on the causes and how to eliminate it. I first had to wrap my head around terms like nodal point, rotational axis and parallax errors. I later found out that the correct terminology is entrance pupil and not nodal point. There are loads of information and tutorial on how to achieve it.
I was salivating over a pano package from Really Right Stuff (RRS) could not justify paying over USD $360. After some thinking and I realised that I could use my panning BH-40 Pro II ballhead and MPR-192 rail from RRS.
Really Right Stuff BH40 Pro II ballhead
1. Calculate entrance pupil of lens. The entrance pupil of the lens must be directly above the rotational axis of the tripod to negate parallax errors.
2. Tripod - preferably a sturdy one.
3. Panning ballhead or a panning base. Excellent, the BH-40 has a panning base.
4. Slide rail. Luckily for me I had an old RRS MPR 192 slide rail which I originally bought to do macro photography but was not suitable as the movements were not smooth enough.
This is how I found the entrance pupil of my Nikon 14-24mm. I place my speaker stand in the foreground and align it with a door frame in the background or any straight vertical line. I then look through the view finder and panned the camera left and right and adjust the position of the camera, by moving it either backwards or forwards on the rail. This process is repeated until the foreground and background objects stop moving when panning the camera left and right.
The tripod must be dead level. This is the hardest part of the whole exercise, it takes a bit of time and lots of patience. It can be very frustrating especially when perched on a rock. I discovered that the spirit level on my Manfrotto 055PROB was crap. I wasted a few hours scratching my head wondering why I couldn't get the tripod level. I ended up using a two axes spirit level instead.
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