The background is that I've been trying out a Canon Powershot digital
camera on a tripod with the Canon Zoombrowser software that lets the
camera be controlled from a computer via the USB.

This works well but illuminating the subject (a ragbag of documents and
old pictures) with desk lights using ordinary GLS lights gives a
visible pulsing of light which can be seen in the monitor due to the
50Hz mains frequency. [which means 2 flashes per sec or 100Hz] This
isn't ideal as it clashes with typical camera exposure speeds.

SFAIUI professional copystand lighting is expensive, so looking for a
method of obtaining a smoothed light.

One possibility would be DC lighting, but it needs to be quiite bright.

Another possibility might be flourescent lighting - but does phosphor
coating on the tube provides some lighting persistance?

Any views on feasibility of either (& how to achieve it) or any other
suggestions would be most appreciated.

TIA