Pimp My Light: Light-Painted Knife

You might think I would think twice about PML'ing a guy who plays with guns and knives. But that would be giving me credit for being way too smart.

Todd Brewer made this evocative shot as part of a series of photos for a friend's website. He is clearly being very creative with his light, using a snooted LED flashlight to create patterns of light to draw the eye to key areas of the composition.

All except the most important part: The sharpened part of the blade of the knife, which remains in shadow.

You might think it would be difficult to light the polished blade with the LED flashlight, which is a tightly beamed light source. And you'd be right, if that is what you were trying to do to define its polished surface.

But you wouldn't want to light the actual blade even if you could. And it is the mirror-like texture that will point you to the solution. You do not want to light the steel of the knife. You want to light what the knife sees. Here's how to do it, using that same LED flashlight.

A light-painted photo like this one is done in either total or near darkness, with everything in a fixed position. The camera is on a tripod, the knife position is known and (usually) many tries are completed before you get a light-painted result that you like.

Thank God for digital. Can you imagine doing this on film? We used to do just that.

So, finely polished knife blade positioned and with the room lights on, you look through the fixed camera position while a helper moves a piece of paper around until the knife shows you its reflection cleanly on the blade.

You can do this by yourself, but you have to clamp or fold the paper so it stands up by itself while you go back and forth from paper moving to camera to find the right spot by trial and error.

Paper positioned to reflect in the knife blade, the rest should be getting obvious by now. You are going to light the scene by deftly moving your little flashlight around, and then create the knife blade highlight by lighting the paper with the same light source.

Personally, I would leave that to be the last variable to solve. It is gonna take a few tries to get the scene right. (I say a few - it'd take me dozens of tries.)

But for the final trick - once you get the scene-lighting movements down pat - you paint in the blade highlights.

If you were doing this by strobe, you'd likely just task one small light to hit the paper (which would paint the reflection in the blade.) But you have a moving, dynamic light source, so why not use that to your advantage?

Why just paint the paper evenly when you could paint it in a cool gradient, (by varying the flashlight time different parts of the paper got) making just about any tonal range you wanted in the blade.

(Total control would be yours, muah-ha-ha-ha...)

Once you get the technique memorized, doing other knives would be a snap. And somehow, all of your knife shots would look very different than those of your fellow photogs.

Which is kinda what this is all about, no?


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