Yes, these are pretty much all lit with a single softbox. A basically dark room, with one soft light source off to the side. Standard angle is about 45 degrees off the camera line, but these shots are more like 90 degrees. An umbrella generally won't give this effect, as the light will spill around the room more, and will light the walls. A gridded softbox in a black room will be optimal for this effect.
If you can make a black room, then you can get away with more light spillage. Alternatively, a large room will work well too, so that spillage reflections will have a long way to travel and be minimal. Something like a big gym (lights off) with a dark back-drop - even if the ceiling is white, the reflection will be minimal. In these cases, you can possibly even get away with an umbrella.
However if you have a small room that's not blackened, you'll need a gridded softbox to control the light better. Also, the closer the light source to the subject, the better - because the flash to subject distance will be proportionately larger than the flash-to-wall-to-subject distance. If you have the flash close and control the light spill, you can even shoot these in front of a white background, and it will come out black in the photo!
<-- This shot does use a reflector at the bottom right of the frame, to fill the shadow, so it doesn't have quite the same high-contrast look.
Once you've got the lighting setup, a little post-processing may be used to accentuate the contrast, and turn the almost-blacks into black, but it's mostly in getting the lighting setup right.
Thank you David. I have just invested in a soft box which I haven't used yet so now I get to practice. I would have tried first with an umbrella but now will use the soft box. Thanks for your detailed answer. I guess we can figure this out ourselves with trial and error but it is so much simpler when people can point us in the right direction.
Ta soooo muchly!!!!! May post some results if I am game.
This was shot without a softbox, just a bare flash, so the shadows are a little harsher, but the concept is the same. I shot this in a normal room, so there is stuff in the background, but you just can't see it. The flash was shot through a tube (called a snoot), made from a cereal box. The tube minimises the light spillage, so the rest of the room stays dark. Flash is 90 degrees to the camera line, so I'm looking straight at the flash in this shot.
