Homebrew PCBs

has one of you here tried the arc lamp method?
i have seen a page where a arc lamp was used (i think the link came from 
here).
the outer glass shell was demolished, (which is the filter/converter).
the inner shell in which the arc burns is quartz glass, good to let 
through short UV.

i really wonder what the times are with that lamp.
it is a point source so the "light undercutting" would be less too.
and this lamps are available with quite a lot of wattage.....

ST