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This page briefly describes how to generate figures appropriate for publication in journals such as Journal of Chemical Physics and Journal of the American Chemical Society.

General Issues

Where to put figures: Upon upload, most of the journal sites taking LaTeX documents need the figures to be in the same directory as the .tex source file. Best to keep them that way originally to avoid unnecessary moving around of figures prior to submission.

The Trouble with Figures: Good figures take a long time to produce. They require a lot of trial and error to make them just right. Why? What you see is NOT what you get. In the process of converting your figure to a final, published version, the figure always comes out looking differently than it did on your computer screen or from your laser printer (even if you supply the publisher with the electronic version of the figure....). There are some rules of thumb, immediately below, which can help make sure that the final, printed figure turns out ok.

Size of Figure: Journals generally ask for figures to be provided in their final desired size. Check the size of a figure for the appropriate journal, and make the figure print out in this size. This is extremely easy to do in LaTeX for PostScript figures (see below). Please make sure that similar figures all have the same size as each other. If you're using Gimp, you can easily resize an image by going to Image/Scale Image. Select 300 pixels/in (make sure this is the same for the X and Y resolutions). The width and height boxes should automatically adjust. Make sure they are as big as the desired figure size, or larger. If larger, you can scale down the image now by adjusting the width to about 80mm (for a single-column figure) or up to 175mm (for a double-column figure). If the width comes out smaller than the desired width once you adjust the pixels/inch, you should go back and re-generate a higher-resolution image.

Size of Lines and Points: Features of the graph need to be large enough to be easily discernible at their final, printed size. Avoid line-styles or point-styles with very tiny dashes and dots: these will not be visible and distinct in the printed paper. Avoid tiny open symbols, as these may "fill in" by distortions of the image in the final, printed form. Also avoid extremely thick lines, as these tend to "smudge" in the final, printed form.

No Shading! Shades of gray frequently don't reproduce well. For bar chartes, etc, that are in black and whilte, use simple patterns, such as cross-hatches or dots, and not shading. For pictures of molecules, you may have no choice but to use shading; hopefully the shades you pick will work out ok --- darker gray might be a little better than lighter gray.

Some ACS Guidelines: (Consult the "ACS Guidelines for Authors" for more information). "Original illustrations that do not need to be reduced to fit a single or double column will yield the best quality. Lettering should be no smaller than 4.5 points. (Helvetica or Arial type works well for lettering). Lines should be no thinner than 0.5 point. Lettering and lines should be of uniform density. If submitted artwork must be reduced, larger lettering and thicker lines should be used that, when reduced, the artwork meets the above-mentioned parameters. Complex textures and shading to achieve a three-dimensional effect should be avoided. To show a pattern, a simple cross-hatch design should be used." For TIFF images, use the following minimum resolutions: black and white line art (1200 dpi); grayscale art (600 dpi); color art (300 dpi). Image sizes: single column, 8.25 cm max width, 24 cm max depth; double column, 10.5 cm min width, 17.78 cm max width, 24 cm max depth. Please also see the ACS "Preparing Graphs and Illustrations" for a GREAT example of what NOT to do.

Some JCP Guidelines: Label all figure parts with (a), (b), etc. Avoid any large disparity in size of lettering and labels used within one illustration. Prepare illustrations in the final published size, not oversized. The maximum published width for a one-column illustration is 8.5 cm. Each illustration should be prepared for 100% reproduction in order to avoid problems arising from reductions in size during scanning. This is especially important for screened or shaded illustrations; reductions of screened or shaded originals during the digitizing process introduces an undesirable Moire pattern. In cases where reduction is required, avoid open symbols that thend to fill in and avoid small lettering. Ensure that, in the final published illustration, there is a minimum of 8-point type size (2.8 mm high) for lettering and 0.5-point width for lines. Ensure that lettering and lines are dark enough, and thick enough, to reproduce clearly, especially if reduction is necessary. Remember that fine lines tend to disappear upon reduction.

Technical Issues

Preferred File Formats: The safest bets are .jpg and .pdf formats. JCP will not take .png format. If your files are already .png and you want to convert them, you can do this by installing ImageMagick, which comes with a program called convert. If that command complains about security policies, you may need to edit permissions in /etc/ImageMagick-6/policy.xml.

Generating Postscript from PDF: Adobe Acrobat (the full version, not the Reader program) is able to export a PDF file as Postscript (.ps) or Encapsulated Postscript (.eps). For most purposes, it does not usually matter which of these is chosen. Unix utilities such as pdf2ps do not seem very reliable for producing high-quality images. Note that Postscript level 1 is not always sufficient to convert all PDF files.

Using Gnuplot: This works well and is recommended. Gnuplot will generate postscript figures directly. A single-column figure will come out the right size if you use set size 0.67,0.67. The recommended settings for a color figure are set terminal postscript eps enhanced solid color 'Helvetica' 16. Some samples are included in ~cdsgroup/papers-examples/gnuplot.

Converting Excel Figures: This is a pain in the neck and is not recommended. Excel figures can be converted to PDF using Adobe Acrobat (full version, not the reader). When Acrobat is installed, it should be possible to print to a virtual printer called Adobe Distiller. This is NOT PDFWriter. Do not use PDFWriter, it uses lower resolution. If Distiller is not installed, you might be able to activate it by installing a Postscript printer. Choose options for Distiller to make sure the resolution is at least 600dpi and ``archive'' or ''print optimized'' options are selected. Print out to black and white to make sure artifacts are not introduced when the figure is printed as black and white later. After you use Distiller, PDF files will be generated (usually in an annoying directory like ``Program Files\Adobe\Acrobat4.0\PDF Output''). You need to convert these to Postscript using Acrobat's export feature (see above paragraph). Note that some patterns will not convert properly if you only use Postscript level 1; it may take a higher level. It seems level 2 is the magic compromise. If you later encounter problems incorporating Postscript figures into LaTeX like ``graphic size unknown,'' you may need to export to encapsulated Postscript (.eps) format. To include in MS Word documents, you need to export as an encapsulated postscript file with preview. However, it appears that when you do so, printing the document uses only the lower-resolution preview witout some kind of special effort. (Or perhaps downscaling the full-page EPS file caused too much distortion). Therefore, it appears best to embed the Excel file in the MS Word document directly...

Scaling Figures: Figures intended for JCP should be printed out in their desired final size. If the figure is printed as a whole page, the publisher might re-scan the original printout and reduce the figure for publication, and that can introduce artifacts (e.g., text in the figure might be large enough when viewed full-size, but it could become illegible when reduced to the size for final publication). Scaling is easily accomplished in LaTeX documents by changing height and width in \includegraphics commands. You can also re-scale the figure itself by loading it into the GIMP, then saving it again as a Postscript (.ps) or Encapsulated Postscript (.eps) file. GIMP should ask for the size of the outgoing file. It is also possible to use GIMP to convert other graphics formats (e.g., JPG) to Postscript, but these will not generally scale as well. If you want to make scalable graphics, you might consider using Corel Draw (available on the Windows machine) to make vector-based (scalable) graphics.