Considering the physiological limitations of non-human visual systems, such as their ability to perceive spectral and spatial contrast, is crucial for studying the ecology and evolution of organismal colouration. For decades, spectrophotometry has provided the basis for modelling animal colour and luminance contrast perception and continues to be a widely used approach in visual ecology. Recently, the PAVO framework (Gruson et al., 2019) has introduced a comprehensive collection of functions to R that allow users to investigate various aspects of organismal colouration using visual modelling and, in combination with digital imaging, colour patterns more broadly.
Calibrated digital photography is increasingly being used to quantify colour patterns in nature because it provides an easily accessible, reliable and low-cost alternative to spectrophotometry and hyperspectral imaging. Multispectral image data obtained by digital cameras can be used to reliably model the early processing stages of most currently known visual systems spanning ultraviolet (UV) to near-infrared wavelength information. The Multispectral Image Calibration and Analysis toolbox (MICA) (Troscianko & Stevens, 2015 ) has made the know-how of calibrated digital photography available to a broad audience and its most recent addition, the Quantitative Colour Pattern Analysis (QCPA) (van den Berg & Troscianko et al., 2019) has augmented the platform into a comprehensive framework for the analysis of colour patterns in nature.
This workshop will briefly introduce the basic principles of spectrophotometry and calibrated digital photography, followed by practical recommendations for data acquisition. During the second part of the workshop, participants can choose between practical examples using PAVO and practical examples using the MICA toolbox. The workshop will be led by MICA and QCPA developers Jolyon Troscianko (Exeter University, UK) and Cedric van den Berg (Bristol University, UK), as well as PAVO developer Thomas White (University of Sydney, AUS) and is hosted by Devi Stuart-Fox (University of Melbourne, AUS). Participants can bring their own image data and discuss specific questions and challenges at the end of the workshop.
To gain maximum benefit from the workshop, we recommend that participants familiarise themselves with these tools on the official websites (www.empiricalimaging.com / https://pavo.colrverse.com) prior to the workshop, particularly by reading the publications and looking at general introductions and tutorials (recommended reading: Maia et al., 2019; Stevens et al., 2007; Troscianko and Stevens, 2015; van den Berg et al., 2020).
