What constitutes image manipulation — some general guidance
Image files should not be manipulated or adjusted in any way that could lead to misinterpretation of the information present in the original image. Our policy and figure manipulation checking procedures can be found here. We routinely check figures for all accepted articles. Please be aware that we may also require you to supply us with your original photographic images in the original file format and at the resolution at which they were first created.
We realize that the extent to which figures can be changed as part of normal preparation can pose a dilemma, so have provided some general guidance below on aspects to consider when preparing your figures. For further information, image examples and more detailed guidance we advise reading 'What's in a picture? The temptation of image manipulation' (reprinted in the Journal of Cell Biology, vol. 166(1) 11-15).
Here are some general issues to watch out for, with links to image examples of each below.
Please watch out for these common issues, which all count as unacceptable figure manipulation:
- The introduction, enhancement, movement, or removal of specific feature(s) within an image;
- Unmarked grouping of images that should otherwise have been presented separately (for example, from different parts of the same gel, or from different gels, fields, or exposures);
- Adjustments of brightness, contrast, or color balance that obscure, eliminate, or misrepresent any information;
Poor-quality images may raise figure manipulation queries and/or result in requests to remake figures.
- Please ensure that your images have a resolution of at least 300 pixels per inch (ppi) and appear sharp, not pixelated. Poor-quality images cannot be checked.
- Be careful not to inadvertently reduce the resolution when creating a file in graphics editing software. When opening your image file in graphics editing software, you have the option of setting the size and resolution of the image. Do not set the total number of pixels to be greater than that in the original image (e.g., from the digital camera attached to your microscope) while keeping the image size the same; otherwise, the computer must create data for you that were not present in the original, and the resulting image is a misrepresentation of the original data. The resolution (ppi) can be increased only if the image size is reduced proportionately.
- Spliced gels need a thin dividing line added to indicate the alteration. It is fine to remove a complete lane and splice the remaining lanes together, but the alteration must be indicated by a thin white or black line between the juxtaposed pieces.
- Images must contain the background "noise" they originally contained. The background should not appear as one uniform color. Do not 'clean up' the background of images with rubberstamp or 'wipe' tools to improve the aesthetic appearance, or over-adjust the brightness or contrast so that the background is removed.