Researchers from acclaimed CICERO - Center for International Climate Research have calculated all the emission factors in the the Green Producers Tool. 
The tool calculates both direct emissions as well as the life cycle analysis (LCA).

LCA is a methodology for analysing environmental impacts associated with all the stages of the life cycle of a commercial product, e.g a camera, a car or a light rig.

Firstly CICERO map what kind of materials each product consists of, then they calculate emissions all the way from where and how the materials and minerals are dug out of the soil, estimate the manufacturing emissions, the emissions from transport to your region, and finally they calculate the expected lifetime of the camera.