Alex is dead-on regarding use of an ordinary light bulb in a reflector. I use a 100 watt soft white bulb in a 10 inch photo reflector hanging 2 feet over the vacuum frame. Exposures for grade 2 AZO are in the 8 sec to 45 sec range. (I have dense negatives...on purpose). It is a little weird at first to be lighting up the whole room during exposure. Using an enlarger will take you 20 minutes or more. I also use a light integrator and a modified photo cell to keep exposures consistent. That became required because my wife would be doing laundry in the room next door and every time the dryer was turned on or off, the light would dim or brighten from the line voltage changes enough to have a big effect on the print values.

Bob Herbst