How can I photograph welding?

Question

My partner is creating a sculptural work using MIG welding and has asked me to document the process. I have a few questions regarding how to photograph it?

1. Looking at the arc can damage your eye-sight. Can it damage my camera's sensor? Are there any protective measures I should take?
2. Any tips for capturing the arcs, depth of field wise?

Answer

1. Any sufficiently bright lightsource can damage the camera internals (not just the sensor, the shutter curtains can heat up and deform). However the sparks from an arc welder are very brief so they don't transfer that much heat energy. I wont say you couldn't damage the camera but it seems less likely than for example photographing the sun, which is a continuous light source. If you want to be on the safe side you can use an ND filter on the lens to absorb some of the light. See this question for more information: Can the sun damage the camera sensor? Under what conditions?

2. I would just experiment with lots of different settings, you probably want a longish shutter to get nice arcs. It might look good if the sparks start in focus and transition to out of focus so I'd use a variety of apertures and just see what looks good.

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