You cannot use direct, unmodified flash.
Oh wait.
Yes you can. and sometimes you have to.
Like when you are outdoors and you want to reduce the ambient light, and light your subject with flash. This gives you control over the light. But it is not simple, at first.
- You want to reduce ambient exposure.
- You do this by setting your aperture , ISO and shutter to give you a darker background.
- You start with choosing a low ISO and fast shutter speed. But your ISO cannot go below 100, and if you wish to add flash, your shutter cannot go beyond 1/200th second, if that is your “flash sync speed”. So you set those values. 100 ISO, 1/200th second.
- But… too much light still, on a sunny day. So now you must reduce your aperture to what you are happy with – say, f/5.6.
When you do this you will find that you get darker backgrounds. All right. Not as dark as you would like but not bad.
Now the challenge will be: at 100 ISO and f/5.6, how far will your speedlight reach? The answer: not far. Not if you add softboxes, umbrellas, reflectors or other modifiers, anyway.
So now we are where I thought we would get: you need to use a bare flash.
And that is fine. But take it off camera.
Direct flash is just “OK” if the flash is near the lens. Like in this image of volunteer model Vanessa in today’s class:
Not bad, and well eexxecuted. But there could be more shape to the face, no?
That is why it is often nicer when the light source is off to the side. The face now gets shape, like in this example:
Now, to be clear: light straight into the face is OK – just as long as that is not also where the camera is!
Like this example – this is just fine:
And that is direct flash, unmodified.
So yes – you can do this, whatever anyone else says. Just as long as the light is not in line with the lens.