An $11 43" umbrella from Amazon is some of the best money I've spent on photography. But.... If getting lenses is like heroin, then getting lights and light mods is like crack. Cheaper but harder to know when to stop.
There are a couple of things you can try. If you put something very white in front of the subject but outside of the frame, that might reflect enough light onto their legs. A big white foamboard or reflector would help here. If this is more casual...
Not sure what the question is. Is there a dark bar? That's caused when the camera's shutter speed is faster than the flash sync speed (1/200sec or 1/250sec depending on camera body). If you're using radio triggers, they introduce a slight delay so...
