Figures for journal articles
Carefully chosen and well-prepared figures, such as diagrams and photographs, can greatly enhance your article. You are encouraged to prepare figures that are clear, easy to read and of the best possible quality and resolution.
To make your figures accessible to as many readers as possible, try to avoid using colour as the only means of conveying information. For example, in charts and graphs use different line styles and symbols. Where colours are used try to ensure that:
- there is good contrast between adjacent colours;
- colours are distinguishable if the figure is converted to greyscale;
- different line styles, fill styles, symbols or labels are used in addition to different colours.
We accept that it is not always possible to follow these guidelines, for example with figures that use colour gradient scales to convey information, or for photographic images. As with all figures, it is important to use the figure caption to describe the information conveyed by the figure. See below for further details.
Figures are converted and sized to the journal template as part of the production process for accepted articles, but they are not normally edited further. It is your responsibility to ensure that the figures you supply are legible and technically correct.
Characters should appear as they would be set in the main body of the article. Aim for text sizes of 8 to 12 pt at the final figure size: typically 8.5cm for a small/single-column figure and 15cm for a large/double-column figure. Micrographs should include a scale bar of appropriate size, e.g. 1 μm. Figures should be numbered in the order in which they are referred to in the text, using sequential numerals (e.g. figure 1, figure 2, etc.).
If there is more than one part to a figure (e.g. figure 1(a), figure 1(b), etc.), the parts should be identified by a lower-case letter in parentheses close to or within the area of the figure.
File types
For articles prepared using LaTeX2e, please make sure that your figures are all supplied as vector Encapsulated PostScript (EPS) and linked to your main TeX files using appropriate figure inclusion commands such as \includegraphics. For articles prepared using Word, where possible please also supply all figures as separate graphics files (in addition to being embedded in the text). Our preferred graphics format is EPS. These files can be used directly to give high-quality results, and file sizes are small in comparison with most bitmap forms.
If you are unable to send us images in EPS, we can also accept:
- TIFF
- JPEG
- PDF (and images embedded within PDF files)
- Images/drawings coded using TeX/LaTeX package
- Images/figures embedded in MS Word, Excel or PowerPoint
- Graphics application source files (Photoshop, Illustrator, CorelDraw).
Vector formats
The advantage of vector graphics is that they give the best possible quality at all output resolutions. In order to get the best possible results, please note the following important points:
- Fonts used should be restricted to the standard font families (Times, Helvetica, Courier or Symbol).
- Certain proprietary vector graphics formats such as Origin, Kaleidagraph, Cricket Graph and Gnu Plot should not be sent in their native format. If you use these applications to create your figures, please export them as EPS.
Permissions
Note that it is also your responsibility to obtain written permission from the copyright holder for any figures you have reused from elsewhere. This will also include any figures that you created yourself but have previously been published by another publisher, unless that publisher allows you to reuse them without permission under their author rights policy. Check individual publisher’s policies for details. Many scientific, technical and medical publishers use RightsLink to grant permission. Information on how to request permission can usually be found on the website of each publisher. For further information about permissions and when permission is required, please see the Permissions section.
Inappropriate images
Please carefully consider both the subject matter and provenance of images included in your work before submitting to the journal. If the submitted images could be potentially offensive to the journal’s readership, IOP Publishing reserves the right to request that authors seek alternative images or other means to express the same results before the final version is published.
IOP Publishing will not consider submissions which feature the Lena/Lenna image (a crop of an image of Lena Söderberg from a 1972 issue of Playboy magazine), as the image and its history conflicts with our commitment to inclusivity in science. Alternatives to the Lena image are widely available, see https://www.tandfonline.com/doi/full/10.1080/09500340.2016.1270881 for examples.
Figure captions
Captions should be included in the text and not in the graphics files. Figure captions should contain relevant key terms and be self-contained (avoiding acronyms) so that a reader can understand the figure without having to refer to the text. To make your figures accessible to as many readers as possible, include the main points that the figure demonstrates in the caption. We provide further information and examples on this page.
Figure captions should also reference the source of the figure if the figure has been reused from elsewhere, including any permission statement required.
Need help with your figures?
IOP Editing Services, in partnership with Editage, can help to check and refine all technical aspects of your artwork to adhere to journal requirements, including resolution, colour and image and file size. Find out more about our figure preparation services.