Hudson trained as a photographer and cameraman in the late 1950s, during the early years of the British realist film movement. He assisted directors as eminent as Ken Loach, Mike Hodges and Jean-Luc Godard. He also shot his own documentaries and as an activist in the Workers' Revolutionary Party played a leading role in its film unit. In 1980, disillusioned with the Party's leadership, Hudson moved to Edinburgh where he subsequently became the International Festival's official photographer. Whilst often playful, his photography remained socially committed in the spirit of 1960s realism.