Proposed steps to enable quantitative, reproducible imaging with a mobile phone microscope.

A Standardize illumination source and brightness. B Set focal state on a field with known dimensions or features. C Set exposure and gain using a clear field of view. Use this field to set or select a white balance state; may require resetting exposure and gain to ensure changes in white balance do not result in saturation of a color channel. D Acquire images of samples while keeping capture settings constant. E Information content can be preserved by selecting lossless or high quality compression settings. In addition, multiple images can be used to record additional z planes or expand the effective dynamic range of the image. While many of the features required to implement these steps are not directly accessible in the default camera, they are built into commonly available third-party camera applications or can be incorporated into custom applications.