Previous Tip    Back to Index    Next Tip

Archive of Photography Tips

Reducing Flash Glare

Tip Provided by Dave

When light from a flash strikes a reflective object, unattractive glare bouncing back at the camera is often the result. The reason is found in the Principle of Reflection which can be stated as, "the angle of incidence equals the angle of reflection, but in the opposite direction". The drawing below shows how the principle works. Picture a pool ball being bounced off of the pool table's bumper side. Notice that in Fig. A, when the pool ball comes in from a 30 degree angle (called the incident angle), it will bounce off the bumper at that same 30 degree angle (the reflective angle) BUT in the opposite direction. Now, if the ball hits the bumper directly head on, it will bounce right back (head on) at the pool cue again as seen in Fig. B.

Flash Bounce
The same physics holds true for light from a flash. If you stand right in front of the shiny object and take a flash picture, most of the flash's glare will bounce right back at you and the camera.
This photo shows what it looks like, not very attractive!

Flash Tip

Brainstorm ... let's shoot the plate from a different angle and the glare from the flash will bounce at that same angle, but away from the camera! And here's what that looks like.

Flash Tip

You can see that the theory worked just fine, but the plate no longer looks round, humm it's sort of tall and squished at the sides ... not the best perspective. At least not for a plate. Though it may be perfectly acceptable for a number of other objects, to keep the plate round we need to think of something else. One way to approach the problem is to use a slave flash off to the side, but leave the camera in front of the plate where it should be, in order to get the best perspective.

Here we go ... this is much better. What I did was to bounce a slave flash off of the ceiling to illuminate the plate without flash glare heading toward the camera (there's still a small amount, but it's a whole lot better). To do it, I needed to trigger the slave flash with some of the light from the camera's built-in flash, but I didn't want the built-in flash to make to the plate. So I placed a white file card over the camera's flash, but at a 45 degree angle, so that the camera's flash bounced over to the slave flash to trigger it, but didn't go forward to the plate to create any bounce-back glare from it. Problem solved!

Flash tip

And it worked just as well on this plate too, hummm, maybe we're on to something :-)

Previous Tip    Back to Index    Next Tip