My latest purchase a few weeks ago was a Nikon SB600 speed light second hand, which supports Auto FP Nikon speak for High speed sync. But I’m unsure whether my camera (Nikon D90)is compatible? On YouTube all the videos on Nikon HSS show in the menu higher sync shutter speeds of 1/250 & 1/350 with the words Auto FP next to these values. My max is only 1/60 & no indication of Auto FP. So I’m just not sure. Thanks.