Using Flash with Macros

[Loupey]

Now that you’ve mastered the 4 Basics, here is a really easy technique to add to your arsenal.

First of all, let me say that I think it is a “mistake” (in a friendly, disagreement-over-a-pint-of-beer-kind-of-way) to think that a flash, no matter how powerful, should be considered the main light source. Instead, I think that flash for macros should be carefully balanced with the ambient light so as to make it look as natural as possible while, at the same time, adding just enough detail in the shadows.

The general method here is:

1. meter on the background
2. set your exposure (in manual mode)
3. set your flash to underexpose

The key is to use manual mode (see, there is a method to my madness here) to lock in your basic exposure. Since you all have taken great pains to control the light coming in to your camera, you’ve got to be equally careful of the light coming out of your camera.

For those of you using the built-in pop-up flash (me), set the exposure compensation anywhere from –2 to –1 . This will force your camera to try to underexpose the shot and the only way it can do that is by reducing the intensity of the flash (since you’ve got the shutter/aperture locked in manual mode). Try different levels until you get the look you’re after.

For those of you using an external flash (I recommend getting an off-camera extension cable or wireless transmitter), you can do the same thing if your flash has a variable output mode. The Canon 430EX can be brought down to 1/64th of its full power. Again, play with the setting until you get the balance for the given circumstance.

Because subject distance is so critical with flash and the ambient light levels are always fluctuating, there is a fair amount of trial and error with this technique. But this technique is easy to master and quick to deploy with practice.