Images can also contain artifacts e.g. pixel values and structures that do not faithfully represent the actual scene being imaged. This may or may not be intentional by the person holding the camera. Artifacts can be by-products of the equipment, methods, lighting, contrast, motion and other factors in which the photon data was collected from the scene. Artifacts are also easily introduced when attempting to enhance an image in post-processing. Applications such as deconvolution, sharpening and noise reduction filters and algorithms, non-linear “stretching” of the image that compresses the histogram of brightness values, and other common techniques are notorious for introducing artifacts and falsely altering details.
Astro imaging by professionals and experienced amateurs follow standardized methods of data collection, data reduction (aka image calibration) and processing to avoid the introduction of artifacts. This is also true for imaging in other disciplines such as medicine, biology and, I assume, intelligence and military. But the final image is only as faithful as the skill, knowledge, experience, and integrity of the imaging team and the entities that choose to publicize an image.
If all of the steps taken to collect and process an image are not disclosed or are not reproducible when the raw data is provided to competent people, it can be very difficult to assess the quality, veracity, and faithfulness of an image or video.
As I indicated in a previous post, ETs seem to be very clever in revealing themselves to people who do not know how to operate a camera.
