A7RII recommended settings for long exposures at night

[panogs]

We've been testing the A7RII for long exposures from Gasworks park across Lake Union facing downtown Seattle at night. We chose a windless night, and attached the camera to very sturdy tripod. Shooting a Sony FE 70-20mm at 200mm we have tested various length exposures. all of them from half a second to 10 seconds show a strange softness in the image. Aperture f.8 and focus was locked correctly. I'm assuming silent shooting mode should be turned on, Image stabilization on the lens was turned off, but could it be the 5-axis stabilization in camera that is causing this issue. We do not see a way to turn off the 5-axis stabilization, in the menu is that the "Steadyshot" option?

You help here is GREATLY appreciated. 

[bwud]

Silent shooting drops precision to 12-bit, so for one I'd turn it off.

 

Posting a photo would help with diagnosis.

[Singingsnapper]

Turn the steady shot off in the menu -   Camera (first symbol in MENU)position 8 turn to OFF.  Also make sure that you turn the lens steady shot off too.  I made this elementary mistake last week and many of my shots were soft as a result

[Vetsky]

I actually have steady shot linked to one of my custom keys.  I use it pretty often.