Nonnit wrote in post #17214213
As close as possible for soft light, until the shaft is just outside the frame.
I often start at 1/8 power or 1/4 power for portraits
ISO 100 or 200, 1/160s or sync speed and F 2.8 - 4.0 is a good start for me.
Great advice.
I usually go with about 1/4 power - which will vary depending on your Speedlight, as some are more powerful than others - 1/160, f/5.6, ISO200. Adjust your ISO as needed for appropriate exposure. These settings will kill most indoor ambient, so all you're getting is flash, and any flash that spills and bounces back off the walls and stuff.
If you want to include some ambient, adjust your shutter speed. If you have to go below about 1/60 to get enough ambient, then you may need to increase the ISO and/or aperture, and adjust the flash power accordingly.
Nightfire wrote in post #17214228
OK Thanks. What about the height of the umbrella? I guess higher would cast more shadows under the nose ans lips. If I want less shadows would I need the center at face level? I will hit strobist here when I can.
Thanks again.
Gonzogolf's advice is spot-on - varies depending on how you want the portrait to look.
Check out the various types of portrait lighting - butterfly, loop, rembrandt, broad light, short light, split light. Different lighting styles work better or worse for different people and different faces. There's no one-size-fits-everyone solution.
An easy formula is 45 degrees above and 45 degrees to the side, but this might be too far off axis if you don't have fill from a reflector or second light.
I'm starting to like a good ol' butterfly light more and more: Main light is placed above the camera, but not horizontally far off from camera axis; subject's nose is pointed approximately to the bottom center of the umbrella.