Wildlife field guide books present salient features of species, from colour and form to behaviour, and give their readers a vocabulary to express what these features look like. Such structures for observation, or observational grids, allow users to identify wildlife species through what Law and Lynch have called ‘the difference that makes the difference’. In this article, we show how these grids, and the characteristics that distinguish species, change over time in response to wider concerns in the community that use and make the field guides. We use the development of Dutch field guides for dragonflies to show how the ethics of observing wildlife, the recreational value of dragonfly observation, the affordances of observational tools, and biodiversity monitoring and conservation goals all have repercussions for how dragonflies are to be identified. Ultimately, this affects not only how dragonflies are to be observed and identified, but also what is taken to be ‘out there’. The article is based on a transdisciplinary cooperation between a dragonfly enthusiast with emic knowledge and access, and an STS researcher. We hope the articulation of our approach might inspire analyses of other observational practices and communities.