HUGE thumbs up. Crary historicizes technological vision and illuminates an underrepresented point: things we're taught to think of as objective, such as cameras and vision, are in fact quite subjective and historical. They're ideas first, which means social/cultural ideas, from design to usage. Gradually these cultural ideas plus economic and technological possibility fuse into 'things'. The social aspects get invisibly embedded into these 'things' through myths of objectivity and modern people's desire to be taken care of by machines. When cultural values become things we are conditioned not to see the subjective part. Why? Our primary way of thinking is still the way of the Enlightenment -- from the 18th century -- which loves measuring and equating and separates 'myth' from 'science'. [Which is which? as Roger Waters asks, Do you think you can tell?] Western high culture privileges thinking and seeing over affect and body, imagining they are separate and valuing one over the other. Really it's just an excuse for laziness and cultural arrogance.
Read this book along with Eric Michaels' _Bad Aboriginal Art_ and Adorno and Horkheimer's _Dialectic of Enlightenment_ to begin to see glimpses of Western cultural values and narratives embedded in today's supposedly 'objective' media such as photography, video, TV, vision, etc. Do the work and eventually technology will be a mirror of your own social/historical context.