Instructions for Authors
MANUSCRIPT PREPARATION - ARTWORK
Please read this information carefully to avoid publication delays. All figures will be reproduced exactly as transmitted, so authors must take special care to prepare high-quality files. Check with your technology support personnel if you need help with producing the proper files.
Authors are strongly encouraged to transmit all figure files electronically (see Guidelines for Preparing Digital Art Files
, below). The figure files should include any labels or markers that are part of the figure itself, but not the figure number, title, legend, or notes (they will be typeset separately). The figure number, title, legend, and notes should be provided with the text of the manuscript.
It is possible that a figure file that displays on the author's monitor and prints from the author's printer without any apparent problem may still have coding that prevents it from being embedded in electronically typeset pages. The production office will work with authors to diagnose and resolve problems and produce usable files at an early stage in the publication process.
Over time, the Press has identified a number of common problems that may cause delays or difficulties in processing art, and to avoid these we have compiled the following list of guidelines for preparing electronic figures. Following them will speed up the production of your paper and minimize the risk of problems occurring in the publication process.
Unacceptable Artwork Types
Artwork Created with PowerPoint, Excel, Word, or WordPerfect:
The graphics created using PowerPoint, Excel, Word, or WordPerfect are low-resolution images that are not suitable for professional reproduction. Graphics created in these programs are acceptable only if they are line images, with no gray, color, or shading (see Line Art
Graphics downloaded from the Internet: Graphics downloaded from Internet pages are not acceptable for print reproduction. These graphics are low-resolution images (usually 72 dpi), which are suitable for screen display but are far below acceptable standards for print reproduction (see fig. 1).
| |Figure 1
. 300 dpi (A)
versus 72 dpi (B)
Cropping and Sizing
Your artwork will be cropped and sized for publication. If you want to be certain that a particular area of your image is excluded or included, please indicate where the image should be cropped.
Please be consistent with type (both font and size) within a figure. Since most figures are reduced, figures employing more than one font size may, after reduction, contain both text that is too small to read and text that is so large as to be awkward (see fig. 2). After reduction, all text should be legible but not excessively large. Of course, some variation in the size of letters may be necessary to emphasize elements in a figure or to fit lettering in a limited space; however, please try to use no more than a 2-point variation in your type sizes.
| |Figure 2
, Note the large variation in font sizes used for labels. This makes sizing the image particularly difficult and results in awkward-looking graphics. In contrast, B
uses fairly consistent type sizes, resulting in a more balanced figure.
Please use the same font type for all figures in your manuscript; use standard fonts such as Times, Arial, Helvetica, or Symbol. Sans serif fonts such as Arial and Helvetica are ideal and should be used whenever possible. All fonts must be embedded in your figures or all font type must be converted to outlines (applications such as Adobe Illustrator can do this). If you transmit a figure that uses custom or nonstandard fonts, the characters may appear in a different font or not appear at all. Remember to check proofs carefully to be sure that all fonts in figures are correct.
If the figures in your manuscript contain units of measurement, please label these units consistently. Make sure abbreviations are consistent with those used in the text and the legend.
Avoid placing labels over shaded areas of a figure. Best results are obtained from black lettering on a white background. If the area requiring a label contains shading, it is best to create a white box and place the black label within.
Figures consisting of more than one panel should include uppercase panel designations ("A," "B," "C," etc.). The Press prefers to receive multipart figures assembled into single image files whenever possible (i.e., one file containing all panels, with parts labeled, and arranged so that they will fit on a journal page or portion of a page). Whenever possible, include all panels of a figure on the same page.
Each chart or graph should incorporate a key to any symbols or colors used. Please set the key inside the figure when possible.
All graphs and plots should include axis lines at the top, bottom, right, and left sides of the data, forming a completely enclosed box. This will allow for easier interpretation by the reader. Figures should not include text along the top axis outside of the box, except for axis labels. Any information about the figure should be contained within the figure legend or in the labels that appear inside the box.
Omit any extraneous information, such as page numbers, figure numbers, author names, or manuscript number, from the figure. Figures themselves should not contain a title or text that is duplicated in the figure legend. Figure legends should be included separately with the manuscript.
If the artwork you are transmitting has been published elsewhere or is otherwise copyrighted, the Press must have a letter of permission from the copyright holder in order to use the image. The permission letter should grant worldwide print and electronic reproduction rights, in perpetuity. Permission grants that restrict reproduction to the print edition or that require later renewal are not acceptable. In addition, if the artwork is not your own, the Press will need information about its source. Copyright and source information should be included in the figure legend.
Guidelines for Specific Types of Artwork
Avoid the use of gray or color in bar graphs. Instead, please use solid black, solid white, and patterned (e.g., horizontally or diagonally striped) bars (see fig. 3). Please refrain from preparing "three-dimensional" bar graphs unless there is a compelling reason for the information to be rendered in three dimensions. The information in most bar graphs can be adequately rendered in two dimensions, and making a bar graph three dimensional only obfuscates the data (see fig. 4). Files should be sized for publication, as described in Cropping and Sizing
above. Optimum resolution for bar graph files is 800 dpi when sized appropriately for print publication.
| |Figure 3
. Possible fill patterns for bar graphs
| |Figure 4
. Avoid using bar graphs that appear to be three-dimensional. Both A
display the same information; however, B
is much clearer and easier to read.
Line art is best reproduced when it is a crisp black-and-white image and contains no unnecessary gray shading (see fig. 5). Avoid using gray in line art. Gray areas scan unevenly, which often results in unwanted "moiré" patterns (see fig. 6). If gray must be used in the figure, the figure must adhere to all requirements for halftone images (see Halftones
| |Figure 5
Unnecessary backgrounds and shading obfuscate data. B,
A cleaner version of the same graph.
| |Figure 6
. Moiré patterns. Image A
was made from a scan of a bar graph that contains gray bars and was printed from a standard laser printer. The fine "screen" created by the laser printer cannot be lined up precisely with the screen used by the scanner-which results in uneven patterns, called "moirés." Solid black (as in B
), solid white, and black-and-white patterns eliminate this problem (see also fig. 3
and fig. 8
Avoid thin lines, particularly in figures requiring considerable reduction. Do not use lines that are thinner than 1 point, and do not use the "hairline" width option that many computer programs offer.
If your image requires the use of many lines (as line graphs often do), please choose patterns that are easily distinguished from each other (see fig. 7). Patterns with similar characteristics are hard to differentiate after reduction. Dotted or dashed lines should be thick enough and varied enough to withstand considerable reduction. If possible, avoid using triple-dot-dashed line styles or any variation that uses 4 or more identifying components.
| |Figure 7
. Possible patterns for line graphs
Files should be sized for publication, as described in Cropping and Sizing
, above. Optimum resolution for black-and-white line art files is 800 dpi when sized appropriately for print publication. Optimum resolution for combination line art and grayscale images is 800 dpi when sized appropriately for print publication.
When preparing black-and-white photographs, please follow the guidelines for Halftones
, below. Preparation of color photographs should follow the Color Art
For journals that do not publish color art in the print edition: At the discretion of the journal office, color photographs may appear in the online version of the journal. Black-and-white versions will be used by the publisher for the print version.
Halftones are any images that contain gray. When using gray, make sure to use gray levels between 20% and 80%, with at least 20% difference between the levels of gray, or it may become difficult to distinguish between different elements in your figure (see fig. 8). Use a screen of 80 lpi or lower (coarser) and make the figures as close to final publication size as possible, as reduction can cause levels of gray to drop out. Whenever possible, use different patterns of hatching instead of grays to differentiate areas of a figure. Optimum resolution for halftones is 300 dpi when sized appropriately for print publication.
| |Figure 8
Variation between different shades of gray is often altered by scanning and reprinting. Two shades of gray that are separated by less than a 20% gradation may become very difficult to distinguish. B,
Black-and-white fill patterns result in graphics that are sharper and easier for the reader to understand (see fig. 3
for fill pattern examples).
Photomicrographs should show only the most pertinent area of the material being studied. A micrometer bar or appropriate scale marker must appear on the figure.
Figures that are intended to be printed in color should be prepared as CMYK (i.e., four-color) files, not RGB files (see fig. 9). RGB files cannot be used for printing and must be converted to CMYK, which can result in undesirable color shifts. If authors cannot provide four-color files, the Press will convert the files from RGB to CMYK. In addition, authors should transmit a hard copy of each color figure as a sample of how the colors should look in the printed journal. This is needed because the appearance of a color figure is highly device dependent, and the Press and the printer need to know what colors the author has seen and approved. Optimum resolution for CMYK files is 300 dpi when sized appropriately for print publication. CMYK Encapsulated PostScript (EPS) files created with Adobe Illustrator and Photoshop seem to produce the best results.
For journals that do publish color art in the print edition: Please note that reproduction of color images carries an extra charge. Contact the journal office for current rates. Unless explicit arrangements have been made with the journals editorial office, you will be charged for color reproduction if your figure contains any color at all.
For journals that do not publish color art in the print edition: Art may appear in color only in the online version of the journal. Black-and-white versions will be used by the publisher for the print version. For this reason, if you are transmitting artwork in color please make sure that the colors you use will work well when converted to grayscale. Use contrasting colors with different tones (i.e., a dark blue and a dark red will not work because their tones are too similar; when converted to grayscale the resulting grays will be almost identical).
Guidelines for Preparing Digital Art Files
Figure files should be in TIFF or EPS format. EPS files saved by a commercial-quality graphic program (such as Adobe Photoshop, Adobe Illustrator, or Kaleidagraph) are generally the most reliable. Authors should avoid using applications that cannot save directly in TIFF or EPS format.
Each figure must be a separate file. If you have a multipart figure, the Press prefers to receive these as a single file, with panels labeled within the image, rather than as multiple files. However, if necessary you may transmit each part of the figure separately, along with a README file describing how they should be laid out. If a figure is assembled from multiple images, the images must be embedded in the file, not linked.
Make sure that figures intended for black-and-white reproduction do not contain any color objects. Although color figures usually print acceptably on black-and-white laser printers, unexpected color images will disrupt the printing process, resulting in publication delays. If figures contain any color lines or color objects, the author may be charged for color, even if color was not requested.
All videos must be in MPEG, QuickTime, MP4, or AVI format. For each video file that is submitted with a paper, the author must provide a still from the video published as a figure. This allows readers to have a printed representation of the animation.
The JPEG file format uses a "lossy" compression that, depending on the setting, will render a file unsuitable for print standards. If at all possible please avoid transmitting electronic files in JPEG format. If this is unavoidable please be sure to save the JPEG at the highest quality available and at the correct resolution for the type of artwork it is (see above).