Help- studio flash won't fire with shoe/PC adapter on A7R2

[psartman]

I've tried all the flash modes, leaving it on regular (fill flash), M exposure mode, 1/125 second. I've tried to different shoe to PC adapters, checked position of contacts, tried two different cords into my Dynalite pack. Tested the cords with my meter, they fired. I tried my tiny Godox 350 flash in the camera shoe, it fires. Is there a setting to enable external flash I am overlooking (I saw disable flash as an option, not selectable in M mode.) I'm shooting still lifes with a custom bellows (no electrical contacts through the lens mount), thought that might have something to do with it, but it doesn't fire with a regular Sony lens either. Any suggestions (besides using a radio slave, which I don't have available right now)?

[Username]

Optical slave the studio lights

to your tiny hot shoe flash. If 

this approach creates a stray 

light problem, block the stray 

light but avoid any small box 

or any sort of wrap that heats 

up the tiny flash. 

  

Most optical slaves are using

basically near-IR wavelengths 

so you can also use deep red 

gels to limit stray light. 

[Guest Jaf-Photo]

Sometimes flash has being playing up on my Sony cameras, despite settings being correct. In those cases, a camera reset has fixed the problem. Could be worth trying.