Winning entries are chosen by our judges according to two key criteria: they should be aesthetically pleasing while also conveying an interesting scientific phenomenon.

In addition to the Overall Winner, a Category Winner and Runner-up are selected in each of the five competition categories:

* Astronomy – Images of astronomical bodies or photographs demonstrating astronomical or astrophysical phenomena.
* Behaviour – Images that capture the behaviour of living species.
* Earth Science and Climatology – Images of physical processes or features related to Earth, including its oceans and atmosphere.
* Ecology and Environmental Science – Images illustrating the interaction of species with their environment, as well as the environment itself.
* Micro-imaging – Images created using microscopes or other high-magnification imaging devices.

Each category winner receives £500 (or the equivalent in local currency). The Overall Winner, selected from the category winners, receives an additional £500, for a total prize of £1,000.

The Overall Winning photograph is featured on the cover of a Royal Society journal and the winner also receives a full Article Processing Charge (APC) waiver for their next open-access publication in one of the Society's journals.

The judges' final shortlist is showcased in an online exhibition. In addition, the Royal Photographic Society awards certificates and a one-year Royal Photographic Society Membership to each category winner, who are invited to share news of their achievement through a blog post or social media.