<p>Joe, thanks for taking your time to reply. You bring up all good and valid points.<br /> I should have mentioned that I am almost exclusively interested in the negative FEC, i.e., decreasing the output. Why? In my experience none of the 3rd party dedicated flashes have as precise and as consistent flash power control and output as genuine Nikon flashes. What that does in (i)TTL mode(s) is either underexposes or overexposes. In my case, which is shooting outdoors in the bright Florida sunlight, the flash I have overexposes in HSS mode almost all the time. I understand that if I am shooting with apertures wide open it may simply be impossible for the flash to provide power level that low, but this happens even with aperture closed a few stops. Majority of the time I simply resort to manual flash control and get decent results, but sometimes there just is not enough time from shot to shot to adjust. I know that FEC may not help all that much but I would rather keep it at lowest (-3 EV) all the time and have a lick of flash, then pull the shadows up in the post, than risk blowing out highlights, which we know in digital is a bye-bye. I also know I could stay under the X-sync speed, use ND filters, etc. but if I am going to get a new flash I want to make sure I can at least have some output control in HSS.<br /> Bottom line, I was just curious if anyone that has a third party flash can test and confirm that FEC works in HSS. With the flash I have now the exposure in HSS is exactly the same from 0 FEC to -2.5 stops FEC, then at -3 it looks like half a stop lower than 0., i.e., you can only really use half a stop of negative FEC.</p>