Regarding my own experience, I use my cobra flash in manual mode playing between 1/16th and 1/8th of power regarding the magnification ratio I'm in. 1/16th power is only for focus stacking. 1/8 for single shots. Adjusting settings with ISO between 100 and 250 allows me more flexibility. Stacking at ISO 250 and 1/16 if effective magnification at 3:1. Single shot at ISO100, 1/8 power with same magnification ratio.