how to create black backgrounds

[sai_kiran]

My sister is expecting this week. I would like to photograph her kid. I have been running through flickr on different baby images. Most of the ones that i like are with black background.

But i am really clueless on how to attain such a background.

Posting here, hoping to pick your brains on how you guys do it.

Thanks

[PowerPix]

If you can't get your hands on a real background you can do it in post processing.

1. Cut the baby (or whatever) from the image using the foreground select tool.

2. Fill in the background layer with black.

3. Create new layer with baby and paste back onto the background.

[kirbinster]

One way to do it is to shoot at a very high speed (1/5000th) and small aperature and use flash. Set the flash to just light the subject. In doing so the only light the camera captures will be from the flash on the subject, the rest of the image will be black. You may have to experiment some to get just the right settings.

[sai_kiran]

Originally Posted by PowerPix

If you can't get your hands on a real background you can do it in post processing.

1. Cut the baby (or whatever) from the image using the foreground select tool.

2. Fill in the background layer with black.

3. Create new layer with baby and paste back onto the background.

hmmm.. thanks for the tip.. didn't think of this

[sai_kiran]

Originally Posted by kirbinster

One way to do it is to shoot at a very high speed (1/5000th) and small aperature and use flash. Set the flash to just light the subject. In doing so the only light the camera captures will be from the flash on the subject, the rest of the image will be black. You may have to experiment some to get just the right settings.

Would the on-camera flash suffice? or would i need an additional flash?

[kirbinster]

You would probably want off camera flash. I don't know if on camera will work at high shutter speed, plus you really can't control what area it lights up.

[inkista]

The other thing with using flash is that you have to be sure that none of the light from the flash hits the background, or the background won't stay black. You may have to physically block the light from spreading to the background with a flag/gobo/snoot.

And to use the flash with a very high shutter speed off-camera, you'll have to have high-speed sync capability. (Kirbinster, I think it's actually easier to get high-speed sync with an on-camera flash). Off-camera, if you're not using a cable to connect the flash to the camera hotshoe, that means you'll have to use CLS/eTTL and the proprietary infrared signalling system of your camera/flash. If you're on Nikon and have a D80/D90, you're on easy street: your pop-up has master capability and you just need a single speedlite slave. But if you're a Canon shooter, unless you're shooting with a 7D, not so easy: you'll need an on-camera speedlight master unit (550EX, 580EX, 580EXII or ST-E2), as well as an off-camera slave unit to accomplish this.

Basically, though, you just need to be working far enough below ambient that nothing but what's lit by the flash registers in the shot, so you could also work below X-sync by lowering your iso and/or stopping down the aperture. Whatever settings will give you a black frame without any flash should be fast enough to accomplish what you want to achieve. It's just that if you lower the iso and close down the aperture, you'll be making your flash work harder, or you'll have to bring it closer to your subject.