General information

Figures should be numbered in a single series that reflects the order in which they are referred to in the text.

Authors should prepare figures to be the smallest size that will convey the essential scientific information (maximum 183 mm x 210 mm) and be aware that the final figure size is at the discretion of the journal. For graphs and line art, please ensure that any symbols are of a suitable size for clarity. For photographs, please use a scale bar to show the magnification and give the length of this in the figure legend.

Figures must be supplied as digital files. These can be bitmap images or line art (also known as vector graphics). Bitmap images are made up of pixels and are typically used to display figures that previously would have been captured on film (e.g. light, fluorescence and electron microscopy, gels, and traditional photography). Line art is instead made up of 'paths' that can form shapes and is usually used for schematic diagrams, graphs and molecular structures. Common line art applications include Adobe Illustrator, Canvas, SigmaPlot and Excel.

Remember that, at initial submission, you may submit a single PDF file containing all text and figures. Once an article has been accepted for publication, you are required to submit separate files for each figure (see below for file formats).

Graphs and line art (also known as vector graphics)

To produce a high-quality PDF and print version, we need to edit the text and line information on graphs and other line drawings to ensure that correct SI units are used and that figures adhere to journal style. To enable this process, we need authors to provide their figures in an editable format (EPS) that retains both font and line information.

File format: Our preferred file format for graphs and other line art is EPS. Please ensure that you 'export' or 'save' with included (text/font) information and do not convert to curves or outlines. EPS format can be created from applications such as Adobe Illustrator, Canvas, DeltaGraph, Corel Draw, Freehand, MatLab and SigmaPlot. We also accept PDF files. Please see the tips below on how to create EPS format using your software.

Note that JPEG or TIFF format will not be accepted for graphs and line art and may delay production of your article.

Colour: Supply line art in CMYK mode. Do not use Spot or Pantone colours, and do not assign a colour profile.

Text labelling: Please use 8pt Helvetica (or Arial) font for all labels. Use 12pt Helvetica font and bold upper case (capital letters) for figure panels. Please use bold for headings. Use Symbol font for Greek characters. Labels should be in sentence case. For gene sequences, please use Courier font, as this ensures each letter is the same width.

Line widths/styles: We prefer you to use pen/stroke widths of 0.6–1 pt. If lines are densely packed, the minimum acceptable width is 0.15 pt.

Tips

Adobe Illustrator: if saving to PDF, use Preset 'Illustrator default' check box for the 'Preserve Illustrator editing' option.
Adobe Distiller: in the 'compression' option uncheck 'image down sampling', embed fonts and do not use any security settings.
Canvas: when saving as a PDF, under PDF options, check box to embed fonts.
PowerPoint: printing to PDF may cause conversion errors with loss of patterns or graduations, so save these in JPEG format and follow the guidelines below for photographic images.
Microsoft Excel: avoid using curved dotted lines, as conversion to PDF may generate a solid line.
SigmaPlot: use the 'File', 'Export' option, save as 'EPS (no preview)' and select the Text option 'convert to postscript fonts'. Recommended minimum size for symbols is 6 pt. For line weights, check by selecting the different graph lines that the minimum thickness is 0.6 pt (Graph: Graph properties..., Plots..., Tabs/Axis: Line icon). Do not use SPSS custom fonts to generate symbols as they will be lost on conversion.
GraphPad Prism: Saving as PDF includes vector and font information, so there is no loss of quality. When exporting several graphs or layouts, you can choose to export all to one PDF file or to create a PDF file for each sheet. GraphPad Prism also exports EPS files (check the option to include fonts). Click here for further details.

Combined photographic and line art images

For figures combining photographic images and line art, please follow the guidelines for graphs and line art but use RGB mode.

When combining images from different files, make sure you always 'embed' images and do not simply 'link' them. In Adobe Illustrator, copying and pasting or dragging an image directly from Adobe Photoshop will embed the image. Alternatively, if you use the 'Place' command, be sure to uncheck 'Link' in the dialogue box. For other software packages, please refer to the documentation for that application (frequently there will be a 'link', 'proxy', 'OLE' or 'OPI' option, which must not be used with EPS files).

Photographic images (also known as bitmap images)

Figures that have been captured on film (e.g. light, fluorescence and electron microscopy, gels, and traditional photography) are referred to as bitmap images.

File formats: JPEG is our preferred file format. We also accept TIFF and PDF files. If you are supplying Powerpoint images, you must save these in JPEG format at 300 dpi, which will avoid conversion errors. Please do not print to PDF.

Resolution/image quality: Images should be saved at a resolution of 300 dpi (dots per inch), and any image quality option should be set to maximum.

Colour: Supply bitmap images in RGB mode, since this is how they will be displayed online and this maximizes colour quality. Do not embed a colour profile.

Text labelling: Please use 12pt Helvetica (or Arial) font and bold upper case (capital letters) to distinguish figure panels and medium lowercase for any labels. Labels should be in sentence case.

Colour modes

Images can be generated by RGB (red, green and blue) or CMYK (cyan, magenta, yellow and black) colour separation. RGB generates colours by combining different intensities of red, green and blue light. This is known as colour by addition (combining all three colours produces white). RGB is used by computer displays and is therefore the format we must use for online images. It produces more vivid and fluorescent colour images.

Note that we must convert images to CMYK for production of the print copy. The colours are generated by combining printing inks that absorb different frequencies. This is known as colour by subtraction (combining all inks produces black). Conversion can alter the appearance of some colours, particularly fluorescence, which can appear 'flatter' than that online because of the inherent limitations of colour by subtraction. This is unavoidable and does not reflect a flaw in our conversion process, which is optimized to give the best possible CMYK images.

Image manipulation

Please note that any alterations made to figures using computer software must be consistent with our image manipulation policy. At submission, authors will be asked to make a declaration that this policy has been adhered to.

If evidence of inappropriate image manipulation is detected by JEB, the journal's Editors might ask for the original data to be supplied and, if necessary, may revoke the acceptance of an article.