The photographer John Thomson (1837-1921) used the 'Woodburytype' process patented in 1864 for the images in Street Life in London, including this photograph. This was a type of photomechanical reproduction using pigmented gelatin, usually of a rich purple-brown colour. The process was complicated but remained popular until about 1900 because of the high quality and permanence of the finished images.
Those who pasted advertisements in difficult positions while perched on ladders were paid higher wages than others in the same job. Employees were often paid by the hour unless it was raining (which prevented pasting), when they were not paid at all. There were around 200 people employed in street advertising, including those who would ride round the city to see that the work had been done properly. Street advertising was considered a good alternative to the workhouse (an institution where the poor were housed and given work).
Real or Posed?
The people in the pictures were arranged or posed by Thomson to form interesting compositions. However, the results were often naturalistic because the subjects and surroundings were always authentic.