Blackening aluminium (was Pinhole Photography)

PMcDonal@sma.gov.au
21 MAR 95 08:35:12 EST

Does anyone know a chemical means for blackening aluminium.

I have made some lensboards for my field cameras and need to blacken them.

I know I can use paint, but it doesn't seem to last very long, and while
anodising is an alternative, the nearest facility is about 300 km away.

Any ideas? or should I just get them anodised.

Peter McDonald.
Canberra, Australia