Lighting 101: Bare-Bulb Lighting
As you have already seen, we can the hard light of your bare flash and soften it with an umbrella. We can further soften it by bouncing it off of a wall or ceiling. But we can also turn it into a 360-degree glowing light source.
The old-school term for this is "bare bulb" lighting. That's because older flashes (and most current large studio flashes) have the ability to totally expose the flash tube, allowing the light to radiate in all directions.
Your speedlight can't do that as is, because the grain-of-rice-sized flash tube is permanently housed in its internal reflector an covered with a plastic fresnel lens at front. But we can diffuse the light after it leaves your flash to create omnidirectional, bare-bulb style lighting.
That's just what Strobist reader Janaka Rodrigue did above, using an inexpensive lamp globe from a hardware store. By sticking the speedlight inside, the harsh light turned into a soft, glowing orb. Which made for a beautiful, ethereal portrait.
Many flashes come with a small, white dome (sometimes called a Sto-Fen) that will convert the flashlight-stlye light into a into a bare bulb-style light. It is omnidirectional, but is it still small and harsh. But it will absolutely make your flash act like a bare light bulb. In fact, I used that same technique here—that's a speedlight in the tiki hut, not a light bulb:
See how the light illuminates the inside of the tiki hut and spills in a natural gradient across the ground? I made that happen by using a small dome on the flash to imitate a bare light bulb. I made the photo of my parents to celebrate their 50th anniversary. You can read in more detail how it was made, here.
Also, bare-bulb modifiers can actually give you softer light—as long as you are near walls and/or a ceiling for that omnidirectional light to bounce off of. That's the secret behind commercially produced larger dome diffusers like the LightSphere.
They work well in small rooms with nearby walls, but they are not well-suited for open spaces. Just saying that so you know what they can and can't do. Plus, next time you see a wedding photographer using one outside (and they do that a lot) you can feel just a little bit superior.
Not to say they are not useful. But you don't have to spend $100 on one, either. You can get one for under $5 at your local Chinese takeout—and they come full of hot-and-sour soup as well:
Just wash it out (or not, whatever, I'm a guy after all) and cut a little "X" in the lid with an X-acto knife. Then it'll slide right onto your flash for a friction fit.
These are great to experiment with. Need light to fill a room in all directions? Bare bulb is your mod.
Gonna light the inside of a fridge to simulate that "late-night-snack" glow? Made sure you've already ordered the hot-and-sour soup first.
There are tons of different ways to modify lights, and many have DIY versions you can try for next to nothing. Heck, we're just getting warmed up here.
But for the moment, let's take everything away and play with that harsh bare flash that has previously been the reason all of your flash pictures looked like, well, flash pictures…
Next: Lighting 101: Hard Light