flash

[cyrus2]

I own 2 fuji xe1 bodies and a xt0 body,when any body and lens combo is used with fuji,s ef42 flash or nissin i40 flash in ttl mode on camera the default sync speed is around 15 second.I can manually set 125s on shutter speed dial and shoot manual flash but very slow sync speed for ttl. any one else having this problem ,and any solutions please.

[sacherjj]

I really don't understand the question.  Flash sync is driven by the time that the shutter can be fully open.  Because flash duration is very short, it will freeze the shutter.  So the first shutter has to fully open, then the flash fire, then the second shutter close.  Otherwise you get shadows on the frame caused by it being covered by the shutter.  This is a limitation of shutter design and physics.   With a aperture style shutter, like the leaf shutter on the X100, the flash comes through evenly across the frame at any speed that there is an opening (similar to MF cameras).