Growing up in a 1960's era veterinary practice, one of my tasks was to develop the "x-rays" (more appropriately called radiographs). This involved a darkroom with a faint red "safelight" and dip tanks with noxious chemicals. The celluloid sheet, once exposed to the x-ray beam, was removed from its cassette in the darkroom and placed in wire hangers, then "dipped" in each chemical for a period of time. It could take nearly half an hour before you knew if the image was good. Ideally it should be allowed to dry before being properly read.
Later a machine containing the warmed chemicals would automatically carry the film through the developing stages and even dry it! This process cut the time per film down to five or six minutes. Both of these processes required the sheets to be placed on a light box to be read.
Now, digital radiology has largely replaced film. After an image is taken, it is sent to the computer, within seconds, in a very high density image called a DICOM. Via the software, this image may be manipulated in a myriad of ways to better visualize the details for greater ease of diagnosis. Multiple images may be viewed in mere minutes, while the patient is still on the table. This parallels the advancement from film to digital photography.
To aid in our diagnosis we also have digital thermal imaging. With this tool we can have a photograph of the thermal (or heat) gradients rather than light. This shows which areas are "hot" or inflamed, helping us to better localize the problem.
In addition to digital radiology and thermal imaging, we use a rigid endoscope to project a video image of the inside of tubular structures (especially the ear) onto a television monitor. With this we can show and explain the condition as we are examining the patient. It is valuable in the case of ear infections, ear mites, foreign bodies or masses. Some surgical procedures, such as laser removal of tumors, can be performed through this scope.