The manipulation on photographs were practiced I think since the beginning of photography. It all started long ago before the first computers appeared. In the past photo editing were either retouching done mainly by professionals with ink and paints on negatives or prints, or the other technique known as photo montage.
Technology made a great steps forward since then. Today even advanced computer user with decent knowledge of popular graphic software may do image manipulations surpassing the best examples of the past. It's became common to alter photographs to achieve better quality or just for fun.
But where were one more use of photography retouch in the past which were privilege of the governments: political propaganda. A good examples of this is collected in the illustrated album of unique photographs by David King - "The Commissar Vanishes: The Falsification of Photographs and Art in Stalin's Russia", which impressed me a lot. This album offers a great ability ot look into reality of Soviet era in Russia. It contains great collection of images from the Stalin era, in their original and altered lately state.
Technology made a great steps forward since then. Today even advanced computer user with decent knowledge of popular graphic software may do image manipulations surpassing the best examples of the past. It's became common to alter photographs to achieve better quality or just for fun.
But where were one more use of photography retouch in the past which were privilege of the governments: political propaganda. A good examples of this is collected in the illustrated album of unique photographs by David King - "The Commissar Vanishes: The Falsification of Photographs and Art in Stalin's Russia", which impressed me a lot. This album offers a great ability ot look into reality of Soviet era in Russia. It contains great collection of images from the Stalin era, in their original and altered lately state.
On the upper photograph Lenin is saying a speech in front of Big Theater, Moscow in 5th of May,1920. There is a Trotsky staying on the steps of tribune. Down is the photograph which were widely published in Soviet Union after Trotsky's retreat.
Here is heads of Soviet government with artists of Moscow theater in 1938. Second is the photo published in 1949. The two man disappeared - they are Ezhov and Boyarsky, so called "Public enemies", they were arrested and executed.
Here on the rear seats of auto is Trotsky and his wife Natalja in Georgia in 1924. And the same shot published in 1936, after Trotsky was wasted from soviet history.
This album could be found on Amazon:

The Commissar Vanishes: The Falsification of Photographs and Art in Stalin's Russia







