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To: Terry Arnold Terry, You recently wrote "A colleague of mine is in the hroes of fininshing a monograph on the radulaof Cyraeidae. This monograph is illustrated with several hundred SEM and optical microphotographs. ....... " I don't know if the following is likely to be of any use to you or your colleague but here goes: I'm a Brit avocational paleontologist working with a range of fossil groups from the lower Cretaceous (Albian) Gault Clay of South-East England. 1. Working with a CCD Camera connected to a PC Mainly (but not exclusively) for scanning tiny shark teeth (from 0.5mm upwards) I have recently set up a 500,000 pixel CCD camera onto a Meiji trinocular low-power microscope illuminated by a Schott fibre-optic KL1500. This is connected via a Video Logic frame grabber (Captivator Pro for VMC) into my PC (a custom built Pentium 133 with a big hard drive (4Gb)) using a software programme called "TV-Snap" which is, in turn, connected to a Lexmark Optra R plus 1200 DPI grey scales laser printer. The image from the CCD onto the screen is excellent. Everything depends on how you set the lighting up. I reckon they are comparable with those produced with a regular optical camera (other than the highest quality cameras) and exceptionally with an SEM. The TVSnap programme lets you "snap" the image, then select an area immediately around the fossil, snap the area then save the snapped image to a file. Because the images are individually quite small (0.5Mb to 0.8Mb) I move them via the clipboard into a suitable programme (A Corel programme, Paint Shop Pro or into a Word 7 document). I tend to use the Word 7 option most because it is clean and convenient - by setting up a page format then using the "Insert Frame" option and pasting into the frame. You can size it, move it and so on and by double-clicking the image can rotate, insert text etc. If I need to edit the image then I use the tools in Corel Draw, Corel Photo Paint or PSP. With practice and a few good tips I'm able to produce some near photo-quality, images of the teeth (from between 0.5mm up to 1.5cm) and the depth of field is also pretty good although I have still some way to go. I print the images directly onto quality paper such as used in copy shops on colour photocopiers (in the uk costs around pounds sterling twenty-three for five hundred sheets). Paper with a shine to it gives an even better photo-like image. The Optra R plus is a true 1200 dpi printer. I've been using it for about four months now and have been surprised with the quality of the output (as has anyone who has seen it). It takes around two minutes to print out a 6Mb A4 page (which would usually have around eight views on it). Incidentally, I also get very good results with other tiny fossils that I am recording (gastropods, ammonite protoconches, fish otoliths you name it and even individual forams and ostracods come out well (the latter nothing like true SEMs) but the best results tend to be around the 4 to 10 mm size. 2. Working with a HP Scanjet 4C 2400dpi flatbed scanner For larger fossils (from about 2cm upwards) I use a flatbed scanner. It lends itself to practically any size that will fit onto the scanner and works with all fossil groups from teeth, gastropods, lamellibranchs and so on. The only limitation is the power of your PC (Speed, Ram and Memory). Here its best to use an example so if you will forgive me: I'm very interested in lower Cretaceous (gault) ammonites and have been for as long as I can remember so I am spending a lot of time scanning and producing plates of specimens from my and some friend's collections. These tend to be quite small (between 2cm and 7cm - the straight heteromorph ammonites up to 12cm). The ammonites vary from unornamented planulate to very inflated tuberculate - the heteromorphs exhibiting varying degrees of coiling and curvature. The HP 4C working through the PC and out again via the Lexmark is really quite remarkable! It copes with lateral and dorsal views of the ammonites in much the same way as an optical camera. The depth of field on the side of e.g. an inflated species of Euhoplites (say, Euhoplites proboscideus, Spath) is every bit as good as any photographic image when scanned, zoomed, scanned again and displayed on the screen particularly when viewed in millions of colours. The rub is that the images can take individually a lot of memory. Scanning a 5cm dia ammonite at 1200dpi as a sharp black & white photo usually takes around 5 to 6Mb so a plate of four ammonites is up to 24Mb and this begins to take a lot of time to move around and format for the printer. Having said this a 5cm ammonite scanned at 1200dpi when put into Corel Photo Paint would fill half your room so the difference in print resolution between a 5cm ammonite scanned at 600 and 1200 is barely discernable and 300 dpi produces a pretty good image too. To create a more permanent personal record I am having the plates of ammonites put onto CD ROM. 3. Your friend's monograph The flatbed scanner procedure should work well with his photographs and if tied in to a 1200 dpi printer I guess would do the trick. I will experiment with a few of my own Scanning Electron Micrographs these next few days to see how it works. Finally, I'm still very new at this and am learning all the time. If you would like me to send you (or any other interested party) a paper copy of the kinds of images I'm obtaining then I'd be happy to oblige - just let me have your address. Regards Jim Craig "Toliapicus" Augustine Road Minster-on-Sea Isle of Sheppey Kent ME12 2LZ UK e-mail: jim.craig@dial.pipex.com (hv89@dial.pipex.com) tel: + 44 (0) 1795 875542
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