I see people comment about changing the curve levels. can anyone tell me what this does etc? is it to do with the amount of a colour in the picture?

Thanks

Ctrl + M in Photoshop on a PC.
It doesn't alster the colours, it alters the contrast and the brightness of the shadows/midtones/highlights. Try forming it into a very slight 'S' shape to boost contrast.

This may help you saxondale. Curves is a very good tool to master. Allows you some serious power over your images.

http://www.dphotojournal.com/understanding...s-in-photoshop/