Hi, I find that for me, aligning the horizon with the lower straight edge of the image as it appears in my viewfinder works for me. What I have found out is that the free download 'Picasa' is brilliant for correcting tilting horizins. You just click the appropriate button and a grid overlay appears over your image with which you can compare your taken horizon. You then just click left or right and your image will lign up perfectly with the grid overlay until you are happy with it, resulting in a correct horizon. Picasa is a very simple editing tool and does most things that are needed, I tried Gimp once and gave up. All the best, Mike.
Originally Posted by magbrin
Humility is an endearing quality and gains many friends, whereas arrogance loses them. Mike, 2012