I just purchased a Godox X2T-N transmitter for my Nikon D5100, along with a Godox TT600 speedlite.
Playing with it I noticed pictures were cut in half horizontally, the upper part being more illuminated than the lower half. At first I thought it was a camera issue, but after some checks I eventually figured it was a synchronization issue : there is a latency between the flash light and the shutter closure.
The setup is as simple as possible with these three elements : the transmitter is fixed on the camera hot shoe, the flash set as slave (S1) in group A, channel 1.
The camera shutter speed is set (in manual mode) to 1/200 (which seems to be the highest shutter speed authorized when the transmitter is mounted), and the anti-red-eye is disabled. The trigger is set to high-speed sync (although I actually first noticed this in second-curtain sync mode). Camera exposure delay mode doesn't improve things, and neither does the X2T delay setting.
I saw the Godox download page has a fix for "the problem that when setting the shutter to high-speed sync and shooting continuously in 1Dx and 1DxII cameras, the shutter sometimes will return to low speed" on the Canon version of the transmitter, could this be a similar issue ?
Anyway, before attempting to contact Godox I wanted to know if there were other settings I could possibly check to cancel this lag, or if there was any workaround besides reducing the shutter speed ?