Hi Mark,
Thanks very much for your comments! In terms of software, I currently use Photoshop CS5. For the horizon, I normally just overlay the grid and use that to check it's level... I maybe didn't do that on this one, as now you mention it, there is a definate down-tilt to the right...
With regards to barrel distortion, I honestly struggled to see what part of the image you can see it! Now though, yes, the horizon line does also have a slight curve to it.
I'm suprised to see it though... the shot was taken with a Sigma 20mm-40mm f/2.8 lens, so I would have thought it would be less susceptible, given that the focal range is surley best suited to landscapes and the like...
I seem to recal I set the exposure using the shutter speed, rather than the aperture, so next time I'll definately use your advice for setting the hyperfocal distance - it's something I've read about many times before, but never put into practice! I'll also delve deeper into my camera's custom menu... hopefully there's a 'Mirror Lock Up' function in there somewhere.
You're views have been very much appreciated.
