Eclipses and equinoxes, solstices and midnight suns—these are the celestial subjects of photographer Chris McCaw. But his photos reveal more than just beautiful representations of what any knowledgeable sky-watcher could see.

The photographs McCaw makes bear the actual burn marks of the sun as it passes through the sky.

How does he do it? “The principal is the same as using a magnifying glass to burn a hole in a leaf,” he says. “Only I use a really big lens and the focused light from the sun to burn its path into old gelatin silver black-and-white photo paper where traditional film would go.”

Since the image is being burned into the actual paper as the sun moves, the exposure lasts as