Image manipulations that change the journalistic content of a picture or a document must be clearly perceptible to the viewer/reader who by no means must be misled.
If it is not immediately clear that a picture has been manipulated, this must be clearly indicated in a caption or in an accompanying text.
If moving pictures are manipulated to the extent that they do not show any more what the camera has recorded, this must be made explicit to the viewer in an accompanying commentary or by means of subtitles. The same concerns re-enacted scenes and reconstructions.
Archival material must always remain recognizable as archival material when its use might mislead the public to think otherwise.
Manipulation of photographs and picture material is an old phenomenon. It can be carried out as superficial technical manipulations and image corrections, such as exposure, retouching or cropping. But thorough alterations through which the content of the image changes are possible as well. Through the digitization and by means of the computer and computer programs it is possible to carry out more extensive, very realistic manipulations which are difficult to recognize as such. The possibilities comprise even virtual pictures and photographs. Image manipulations can be carried out at different phases of the news process.
Because of the improved technology there is a risk that a manipulated picture, a photomontage or a revised document are regarded as "authentic" by the picture consumer. Images can be manipulated for the purpose of distorting the reality, both when images are reproduced and when they are perceived. Altering the journalistic content of a picture or a photograph can be misleading, if it is not clear to the viewers that alterations have been made. That jeopardizes the credibility of the image and that of journalism.
The same risk is present when archival pictures are used. Archival material becomes quickly obsolete and that material might give a wrong impression when used carelessly. In this case, too, the viewer can be misled if it is not immediately clear that dated pictures are used.
If the viewer or the picture consumer cannot immediately see that he is being exposed to thoroughly altered images or to archival material, this has to be made explicit in an accompanying text or commentary.