[Just checked out your website - very cool work]
Repeated in darkness.
Attempts to get near/at point of over exposure:
[52mW] f16, Iso3200, 30 seconds:
[26mW] f11, Iso3200, 30 seconds:
Alternative settings:
[52mW] f8, Iso400, 30 seconds:
[26mW] f5.6, Iso400, 30 seconds:
SMOKE (kind of...