In Joe McNally‘s CLS video it showed him using a ballhead to align the flashhead along the umbrella stem axis. Made sense that it would distribute the light more evenly; so I bought the rig. Here’s the test results – you decide.
As pointed out in the note above, I forgot the diffuser.
The ballhead is the Manfrotto Lite Tite Swivel+Umbrella Adapter 26
The coldshoe is the Stroboframe Shoe-type Flash Mount Cat. No 300-SHO
I consider this as a ‘nice to know’ experiment only. With the inherent spill associated with shoot through umbrellas and with the difusser on the speedlight the coverage appears to be good. One additional advantage I found with the ballhead set is the ability to quickly rotate the flash body to align the IR sensor to face the camera.
I’ll know better after I field test it.