What is the 500 Rule in Photography?

If you’re into night sky photography in any way then it’s only a matter of time before you run across somebody talking about the “500 Rule” – sometimes referred to as the “rule of 500.” It’s a classic photographic rule of thumb that most experienced photographers will commit to memory for when they are out shooting at night and want to capture one of those beautiful images of the Milky Way that tend to blow audiences