A fast GNU method to draw accurate scientific illustrations for taxonomy

Abstract

Nowadays only digital figures are accepted by the most important journals of taxonomy. These may be produced by scanning conventional drawings, made with high precision technical ink-pens, which normally use capillary cartridge and various line widths. Digital drawing techniques that use vector graphics, have already been described in literature to support scientists in drawing figures and plates for scientific illustrations; these techniques use many different software and hardware devices. The present work gives step-by-step instructions on how to make accurate line drawings with a new procedure that uses bitmap graphics with the GNU Image Manipulation Program (GIMP). This method is noteworthy: it is very accurate, producing detailed lines at the highest resolution; the raster lines appear as realistic ink-made drawings; it is faster than the traditional way of making illustrations; everyone can use this simple technique; this method is completely free as it does not use expensive and licensed software and it can be used with different operating systems. The method has been developed drawing figures of terrestrial isopods and some examples are here given.

Drawing setae: a GNU way for digital scientific illustrations

“…In my opinion, the presented method brings an enhancement to the previous drawing procedure (Montesanto, 2015). Figure 5 clearly shows diff erences in drawing setae with the present method.…”

“…Figure 5 clearly shows diff erences in drawing setae with the present method. Stronger and/or single setae should be drawn following the technique in Montesanto (2015).…”

“…1F); • choose the appropriate brush: N. 2. Hardness 075 (the same in Montesanto, 2015); • left click on the "Dynamics" butt on in the Tool Options panel (Fig. 2A); • choose "Basic Dynamics" from the menu; • in the "Fade Options" bar, choose a value from 50-90, depending of the length of the seta that should be drawn (see aft er) (Fig.…”

“…Th erefore, to complement the previously cited work (Montesanto, 2015), I here propose a free-hand way to quickly draw small setae with a single movement of the mouse.…”

“…Th is method (Montesanto, 2015), exclusively based on raster graphics, uses a completely free soft ware (GNU Image Manipulation Program, GIMP). It is ordinarily used by myself and other colleagues to illustrate species (e.g.…”