1. A system for rendering an image using a light field image file, the system comprising: a processor; and memory containing a rendering application and a light field image file; wherein the light field image file is structured using the Exchangeable image file (Exif) format and comprises: an encoded image, where the encoded image is generated based on image data captured from a reference viewpoint using a first imager; and metadata describing the encoded image stored within an application marker segment within the light field image file; wherein the metadata comprises a depth map that specifies depths from a reference viewpoint for pixels in the encoded image, where the depth map is generated using at least the image data captured form the reference viewpoint by the first imager and image data captured from a different viewpoint to the reference viewpoint using a second imager; and wherein the first imager and the second imager are contained in a camera array comprising a collection of imagers designed to function as a unitary component, where the collection of imagers comprises at least two heterogeneous imagers; and wherein the rendering application directs the processor to render an image by applying post processing to the encoded image using metadata contained within the light field image by: locating the encoded image within the light field image file by locating a start of image marker within the light field image file; decoding the encoded image; locating the metadata within the light field image file; and processing the decoded image by modifying the pixels of the decoded image based on the depths of the pixels indicated within the depth map to create a rendered image by applying a depth based effect to the pixels of the decoded image.