So my first substitution was wrong (H=0.08). I wasn't using the equation properly.

Need to rethink this.

I'm not understanding what this formula does. H is exposure in lux-s. Then on the right side of the equation we have I in lux, and then the other term which is the reciprocal anti-log of D. Somehow multiplying I (lux) by the reciprocal anti-log of D gets us to lux-s? How?