Hello Alex and crew. I'm off to fabulous Aiyanar Resort, Anilao in a few weeks and wanting to sort this problem out as I would prefer to use a diffuser using macro. Actually I'm leading a group of 32 and am really looking forward to some great critter dives. But....I'm having problems with the Inon .5 stop diffuser on d180 strobe. I find that, if I use this diffuser it underexposes everything by about 4 stops (not .5) but only when I use the strobe on auto. On auto this diffuser cannot work properly with this strobe. If I return the strobe back to manual function full power is restored and I get perfectly exposed shots with very little loss of power (.5 stop if fairly difficult to pick). It is as if the auto sensor gets too much light fed back into it by refraction and 'backsplash' off the diffuser. There is a small hole in the diffuser to allow the sensor to function, but I think there must be a considerable light flow backsplash that fools the sensor into shutting the strobe off prematurely. Anyone else experience this. Any comments..? I'm thinking of either drilling the hole out larger the avoid light backsplash into it, or perhaps blacking out the edges of the whole. Any comments..?