My Vivitar 285 has a half power and quarter power setting... Would setting the power output at 1/4 be the same as 2 stops less light?? My flash photography, as of now, sux.... Completely harsh, blown highlights. I should probably read a book, but I just assume get a clue from one of you guys and test shoot. I use a diffuser shield and I shoot with a flash bracket, I think I may just be using too much juice.. Any suggestions or God forbid, have any good book recommendations??