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Given that roughly half of all paleontological papers contain no photographic images at all I think Tom's concern with image quality is perhaps an over-reaction. Surely there are enough examples of truly stunning graphics on the web to convince even the most jaded skeptic that, in principle, pictures present no problem for a web-based EPJ. Can "ordinary" paleontologists archive adequate results with a minimum of bother? I think they can. Before we start, however, let's be clear that almost all of the plates and greyscale images we see in print journals are halftone screens that dissolve into variably-size dots if you get too close. Try it! This is not the same type of resolution you get with a photographic print; it is much lower. The question we should be asking isn't whether electronic images can achieve photographic quality resolutions. (they can, but the file sizes necessary are quite large and print-journal graphics are not held to this standard). Rather we should ask whether electronic files of reasonable sizes (say <500k) can represent sufficient detail to be useful as a mode of technical illustration. Here's an example. The original plates for... MacLeod, N., 1993, The Maastrichtian-Danian radiation of triserial and biserial planktic foraminifera: Testing phylogenetic and adaptational hypotheses in the (micro)fossil record: Marine Micropaleontology, v. 21, no. 1, p. 47-100. ...were prepared as digital images using a combination of scans from Polaroid SEM photomicrographs and direct digital SEM photomicrographs. Because of limitations in the publisher's ability to use direct digital images in the production of the journal, the final images used were LaserWriter printouts (600 dpi) of the original digital images. These printouts were deemed of sufficient quality for publication by the Marine Micropaleontology editor, the ms reviewers, and the publishers (Elsevier). However, as you can see if you compare the version of an original plate from that paper (Plate 1) that I have placed at this address... ftp://mailserver.nhm.ac.uk/paleonet/Visions_of_the_Past/Plate.jpg ...to the version that actually appeared in the journal, the digital image is of much higher quality. [Note I have modified the font used on this electronic plate to distinguish it from the illustration that actually appeared in Marine Micropaleontology.] If you download this image and open it up in a graphics software package that has the ability to reset your monitor's resolution from color to greyscale on the fly (e.g., Photoshop), you'll see another increase in resolution. Moreover, this is a version of the original image file that is of much lower quality than the original. Specifically, this file has reduced in size and written in a compressed graphics format (jpeg) to facilitate rapid download times. This procedure reduced the file's size (= quality) from 1.57Mb in the original to just 157k in the ftp version - well below the 500k I threw out as a "reasonable" size for technical graphics. I hope this demonstration convinces you that the image quality available using current digital technology is adequate for the purposes of technical paleontological illustration in a completely electronic format. Norm MacLeod ---------------------------------------------------------------------------- Norman MacLeod Senior Scientific Officer N.MacLeod@nhm.ac.uk (Internet) N.MacLeod@uk.ac.nhm (Janet) Address: Dept. of Palaeontology, The Natural History Museum, Cromwell Road, London, SW7 5BD Office Phone: 0171-938-9006 Dept. FAX: 0171-938-9277 ----------------------------------------------------------------------------
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