The use of low cost compact cameras with focus stacking functionality in entomological digitization projects.

Jan Mertens,Jonas Merckx,Wouter Dekoninck,Martijn Van Roie

doi:10.3897/zookeys.712.20505

Abstract

Digitization of specimen collections has become a key priority of many natural history museums. The camera systems built for this purpose are expensive, providing a barrier in institutes with limited funding, and therefore hampering progress. An assessment is made on whether a low cost compact camera with image stacking functionality can help expedite the digitization process in large museums or provide smaller institutes and amateur entomologists with the means to digitize their collections. Images of a professional setup were compared with the Olympus Stylus TG-4 Tough, a low-cost compact camera with internal focus stacking functions. Parameters considered include image quality, digitization speed, price, and ease-of-use. The compact camera’s image quality, although inferior to the professional setup, is exceptional considering its fourfold lower price point. Producing the image slices in the compact camera is a matter of seconds and when optimal image quality is less of a priority, the internal stacking function omits the need for dedicated stacking software altogether, further decreasing the cost and speeding up the process. In general, it is found that, aware of its limitations, this compact camera is capable of digitizing entomological collections with sufficient quality. As technology advances, more institutes and amateur entomologists will be able to easily and affordably catalogue their specimens.

Highlights

Many museums rely on the help of volunteers for collection work (Flemons and Berents 2012; Holmes 2003)
The picture of the latter retains its sharpness towards the edges (Figure 1B), whereas images made by both stacking methods of the compact camera (Figure 1C–D) are less sharp there
The compact camera and the professional setup are comparable in terms of usability when used for taxonomic studies

Summary

Introduction

Many museums rely on the help of volunteers for collection work (Flemons and Berents 2012; Holmes 2003). One such effort is the digitization of the vast quantities of specimens in the collections (Mathys et al 2013; Mathys et al 2015). Time-saving techniques are sometimes used, for instance whole drawer imaging (e.g., Mantle et al (2012)) These techniques have major limitations and the resulting images often lack the resolution necessary for taxonomic accuracy or it fails to capture all required information (e.g., limited angles in which the specimen was shot or specimens covering the labels, Brecko et al (2014); Hudson et al (2015))

Methods

Results

Discussion

Conclusion