Hi,   I have been using my Subtronic PRO160 strobes (optic fiber) and Sea&Sea YS-D1 with a Nikon D800 successfully up to shutter speeds of 1/320 (always with optic fiber using a manual led trigger that I installed in a Nauticam Housing, with camera flash sync speed set to 1/320 auto-fp).   I've upgraded my camera to a Nikon D850 in a Nauticam housing with Nauticam's manual led trigger installed as default. Yesterday I've tried my Subtronic's PRO160 UW for the first and they only were abl