So, the question always comes up, and the desire always comes up in photography - I want a beauty dish - or I want a 8 foot octabox, or I want ____ modifier! It's asked by experienced photographers, people who are new and learning, and everyone in between, and it's really a hard question sometimes because at the surface we think all the modifiers are really different - when in truth the differences are mostly folklore and stories.
Now, the target audience are those who are looking for a bit of info on how different modifiers work for headshots. I don't take credit for knowing everything, and all of this is just my opinon.
So let's start out with umbrellas, they are what we all start out with, and work well for the most part. You can go though all kinds of fashion magazines and see them used, and I'm sure you can find them in a few advertisements. They are basic, cheap, and they work.
So here is a shot with umbrellas.
Now, granted I did shoot this a little flat, but the shot is still dynamic, the shadows are still soft, and all in all it's a decent shot for what it is.
So that's an umbrella, and again they work great. The only downside is they catch the wind a lot outside, and the catchlights may or may not be desirable, not to mention that the spill can be a little much if you need tight control.
Now lets move on to softboxes, and I guess I'll throw in octaboxes as well since they are the same thing. Everyone ends up getting one or two of these and they are the natural progression from umbrella. They work great, and project a nice "window" of light on the subject. Also, they can be gridded to control the light - which in my opinon is one of the main selling points to them.
I have a few shots done with them, so you can see the differences from the umbrella one - and again these are just headshots.
Again, as with the umbrella, and at reasonable distances, they give nice even light, even shadows, and as with my work at the time the shots are a little even and less dynamic than I do now. However, the differences between the two modifiers are minimal, and at this point I don't see a reason to go out and buy a softbox over umbrellas - unless you needed grids to help direct the light, or needed a little more spill control.
Ahhh yes, the Beauty Dish! So this seems to be one of the holy grails photographers search for, and the end all be all of beauty lighting. There pretty much the same as umbrellas when it comes to spill, other than they can hang out in the wind a lot better outdoors than umbrellas - and for that they are what I use outside almost all of the time. You can also grid them to get some tight control over their light, which helps inside if you need that kind of control.
Here are a few shots with beauty dishes, and keep in mind they were a clamshell setup, and had a light behind them for fill. Now, I never said this was a scientific test, just showing examples of real world shots.
Now, granted they are a little more dynamic than the others, the shadows are a little deeper - but that's really about it. Also, that difference could be more to do with how I light the first few examples rather than anything specific with the beauty dish... So it's more like going on a drive and having many different roads, all pretty much the same distance, that will get you to where you're going.
RingLights! This is the other quest that people seem to be on, and it's one of the lights that I don't have at the studio. They can be great for fill, they can also be cliche very easily, as well as they can be boring after a while.
This wasn't shot with a ringlight, but the effect you would get is about the same as far as it being even light coming directly from the lens.
So finally, two more examples...
I shot my friend in natural light one day when it was overcast and got this...
It's pretty similar to the first few examples I posted of softboxes and umbrellas, where I was going for even light and less shadows. Which helped me form the opinon that almost any lights will work for almost anything, and that half of the style is in the retouching in post. (retouching is another topic)
The last example is this, which was shot with a 8 foot octabox at my friends place in NYC.
It looks pretty close to the beautydish shots, the shadows are deep, the light is pretty even, but it's done with a huge softbox rather than a beauty dish or something normally associated with this style of light. So again, anything can be done with any light, it's just a matter of how you use it.
Things to look for when you're looking at pictures! The catchlights give things away, pay attention to them when you're reading all those magazines and looking at all these advertisements we have around us. They tell you a lot about how the shot was lit, what modifer was used, and how far away it was.
I may come back to this topic, but again for headshots it really depends on your style and what you're comfortable using and less on what type of light it is. It also depends on how you retouch, since that plays a vital role in your style and image.