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Black flickering bars


Willen
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I would recommend against using a mix of LEDs and incandescents. Their color temperatures are usually different, which can cause oddly colored shadows that can't really be fixed in post. (This can be a useful effect if you're trying for an artistic photo, but for a photo for record, it's usually not what you want.)

 

If you're using flickering lights (LEDs and fluorescents, for example), you can often get better results with less light. If the shutter speed is much longer than the 1/50 - 1/60 second flicker period, the light will average out over the exposure.

 

The one thing you have to worry about is your camera automatically boosting the ISO (amplification) in low light, which can result in significant digital noise. If you can turn off any automatic ISO adjustment, that isn't an issue.

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Position of shadows is determined by the position and number of lights.

 

Depth of shadows is determined by the relative power of each light source, which, in turn, is determined by the inherent power of the light and the distance from light to subject. Remember that light falls off proportionate to the square of the distance, so if you double the distance you'll drop the power by a factor of four.

 

Power falloff from near side to far side of the subject is determined by the distance from light to subject. A closer light will have a faster falloff.

 

Sharpness of shadow edges is determined by the angle subtended by the light source. A large light (either a bulb very close or a diffused light farther away) will have a softer shadow edge. And the closer the light source, the softer the edge, because the angle subtended rises as the light gets closer. Many people find this counterintuitive.

 

You'll have to read your camera manual to determine whether a half-press will set exposure and focus or just focus. (With some cameras, you can change the behavior.) That said, you would be better off dialing in exposure compensation; it's less fiddly. As noted above, that will affect the overall exposure, not the shadows, though.

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Thanks for the detailed explanation on shadows. I figured that out, and if a half-press sets exposure, I could eliminate the shadows latter by changing the light setup. Tricking the camera.

 

But I don't know if that would be of any help anyway.

 

All this talk has me wanting to by a decent camera now!

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For a really simple light setup, try two incandescent lights, one just out of frame at 45 degrees off axis on one side and the second 45 degrees of axis on the other side and 40%-100% farther away from the subject.

 

Incandescent means no flickering and a good color rendering index. Close means large with decent shadow falloff. And the second light fills the shadows a bit, but not so much that you lose the shape of the figure.

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