That was my bad it is 1/2 as you point out. We are both learning this at close to the same time. I just tried setting the dial between 1/16 & 1/2 (hoping it would create a setting of an in between value - no luck! The end result was too much light.
I like the effect of the stofen as a diffuser but tweaking the light is the next challenge. Next I will play with adjusting the angle of the flash head with the stofen attached and at the brighter settings. The change in angle should also affect the amount of light entering the field of view.
I look forward to seeing your results too.
I will pass along anything that I come up with on this combination. But you have an unfair advantage- it's warm where you live
. No bugs and such in the snow! Gerry