Nature photographer Erez Marom had cold feet - literally - when he created this image. Standing (with thermal boots on) in the freezing waters of a glacier lagoon in Iceland, he saw an opportunity to capture a unique ice formation in the foreground, distant snow-capped mountains and the Aurora Borealis above it all. In this article he explains how he used focus stacking to get the look he wanted for his final image, ‘Flames of the North’