In terms of literature, Cervantes mentioned in his most recent book that fewer hours of "daylight" have an influence on the number of females produced. He goes as far as saying that 14 hours of light will produce more females then 16, 18, 24 hours of light. There are also other factors like humidity, temperature, and N levels. I believe this information originated from a Dutch seed supplier.
Cervantes admits that although he was initially skeptical that 24 hours of light did anything other than waste 6 hours worth of electricity (I'm paraphrasing), he's now convinced that plants will grow faster if they get 24 hours of light.
The whole female:male window seems like it starts around week 3 of vegetative growth, so I think ideally you could go 24/0 up to the 2nd to 3rd week of vegetative growth and then hit the factors the are known to produce more females with shorter periods of daylight being one of those.
Shorter photoperiods also decrease the time it takes for preflowering. Not speaking from experience, it's just what I've read in books.