Updated 15 June 2005       

Figures

Following are helpful hints for preparing images for publication. Figures FAQ provides responses to frequently asked questions. Refer to Acceptable File Formats for accepted formats for submission, publication and the archive.

• Aim for the smallest possible file size at the acceptable resolution. Authors should strive to convey their point with the smallest possible file size because of varying limitations on bandwidth and disk space.
   
• Resolution for graphic files must be 300–600 dots-per-inch resolution (dpi) for color, gray scale, or continuous tone images and 1200 dpi for black and white bitmap line art.
   
• After saving a graphic file, preview it as saved with a suitable previewer prior to submitting it. For example, to ensure that an EPS image is properly saved and useable, open it in Adobe^® Illustrator^®.
   
• For most graphics with lines and text only, use vector graphics EPS.
  EPS is preferred because it is scalable and one can zoom in without seeing large pixels in most cases. Most vector-based illustration software allows you to save an illustration as an EPS file.

  Note: It is possible to generate an EPS file of enormous size relative to the content (e.g., an EPS illustration containing a false-color image derived from a high-resolution data set). In such situations, the EPS file should be converted to a raster (TIFF) file. Alternatively, a lower-resolution version of the original data set can be used to create the EPS. Use the following formula to determine if the EPS file size exceeds the comparable TIFF file size:

  size = width x height x dpi2 x n/8

  in bytes, where width and height are measured in inches; dpi is typically 300; and n is 24 for color, 8 for gray scale, and 1 for black and white.
   
• For photographic images or equivalent, use TIFF or high-resolution JPEG.
  JPEG is the best format for photos with a large file size because of the automatic compression used, which dramatically reduces file size while still providing good detail.
   
• For false-color imagery, shading, or texture, use TIFF.
  TIFF provides the highest resolution to ensure patterns and shading are maintained, yet it offers lossless compression and thus smaller file size.
   
• For color figures, RGB displays better online and CMYK is required for the print version of the journal. Authors may supply (1) both RGB and CMYK for each color figure or (2) only RGB, which AGU staff will convert to CMYK. All authors have a chance to review the results of the conversion on a figure checksite prior to creation of an article proof.
   
• All lines must be at least ½ or 0.5 point (no hairline rules).
   
• Choose fonts carefully and embed all fonts used. Helvetica is preferred for its readability. Do not use italic. Font size should not be less than 8 point in the final layout size. If special characters are used, create them as outlines or they may not process correctly.
   
• Combine multipart figures or plates, adding letter labels as needed for captions, or provide separate captions for each part. The number of figure files should equal the number of figure captions.
   
• Upload figures or plates separately into GEMS, AGU's electronic submission system. Note that PDFs with figures embedded at the end of the manuscript are acceptable for initial submission but not publication. See Creating a PDF for Peer Review for more information.
   
• To accommodate figures that contain many thousand points of data, all original, unsized figures will be provided for viewing and download from the full version of the online article. These figures are in addition to the faster-loading, lower-resolution figures placed within the article itself.
   

The Cadmus Digital Art Information Web site, http://cjs.cadmus.com/da, gives information on how to save to CMYK, how to set the resolution, and other useful information. Not all file formats referred to in this link are accepted by AGU. Please refer to Acceptable File Formats for accepted formats for submission, publication and the archive.

Animations/Movies

Several file formats are accepted to enable authors to take advantage of the electronic medium by using materials that go beyond the printed page. Information on acceptable formats is available in Acceptable File Formats .

• Compressed video formats are recommended because of size and transmission times.
• Open-source and commercial tools are available to transform raw digital video (i.e., AVI, DV) to MPEG.
• For animated GIF files, authors must also supply the individual TIFF frame images and a README file that includes sequence and speed.
• Authors can supply a single frame for publication in the online and print PDF, where the caption will note that the animation or movie is available in the HTML version. Alternatively, authors can choose to provide only the caption in the PDF versions of the article.

Sound

To date, AGU has had little experience with publishing sound files. Acceptable formats currently include WAV, MP3, AU, and AIFF. Guidelines will be developed based on best practices at the Acoustical Society of America.

Questions? Contact graphics-help@agu.org .