how do i black out my background

i've seen alot of example in the one light thread where backgrounds are black(from lighting technique, not physically black backgrounds)

i have a 430ex2, triggers, and a cheetah 24" softbox,

i've played around with f stop and shutter speed but i either end up with a photo that is way to dark all around or a background that shows(my living room in most cases)

what am i doing wrong?

Use your F stop to get your subject lit properly with your flashes.

Use the shuter speed to control the ambient light. Push it to 200 or 250 to remove most/all of the light except for the flash.

Make sure your subject is 4 - 6 feet away from the background and start there. You may have to pull them further form the background, depending on your particular setup.

Pull your subject away from your background, use a high shutter speed to kill the ambient light, and then make sure that you don't get any light "spilling" from your flashes onto the background. If there's no light on the background, it will show up as black!

To test what cxthree said, take a picture without flash and you should see black (or pretty close to it). If not, keep playing with the aperture, shutter speed, and distance from bg.

Also, keep your key light from spilling onto your bg. Using gobos or barn doors may be needed.

Photoshop is another option...

Thanks,

I tried to type up an explination but I dont want to steer you wrong...

better explained here... http://strobist.blogsp​ot.com …12-position-distance.html

biggest advice I can give is move your subjects further from the background. the closer to the background the easier for the light to spill from the flash on to the background.
also turn that shutter speed up.faster your shutter speed the less ambient light you have showing in while not affecting the light comming in from the strobes.

if there is any light light whichshouldn't be much if any if you do both the above you can burn it out using photoshop.

Keep your background approx 4-5 times the distance of your lights to subject and you'll be fine. The closer you can keep your lights to your subject the easier it is.

Use the highest sync speed.

You don't need high speed sync, its really easy to kill all the ambient @ 1/200th, ISO 100, F5.6. You need to move your light as close as possible to your subject, the closer the light the faster the fall off. Also, move your subject from the background, as suggested about at least 3 times the distance of the light to your subject. Grids also help to control spill.

Dave

Yep run your sync speed up as high as you can to eliminate ambiant light and move your subjects farther away from the backdrop.

Leo

Shutter speed controls you ambient light.. Increasing your shutter speed will decrease your ambient light. Thus making the background black....

As the OP mentioned that in most cases images were shot in his living room, I'm assuming he is referring to a studio type set-up. I assume the problem is with his lighting technique rather than ambient light. If this is so, shutter speeds will not make any difference.

Would be nice if the OP reported back and acknowledged some of the suggestions.

scorpio_e wrote in post #9817352
Shutter speed controls you ambient light.. Increasing your shutter speed will decrease your ambient light. Thus making the background black....

This may work without the use of flash but when using it (flash) HSS for canon is @ 1/250 so once you reach that shutter speed and your background still isn't black then your theory no longer works.

as others have said...

- move subject further away from background
- make sure there is no spill hitting the background
- move light source closer to subject
- increase shutter speed (up to 1/250)
- smaller aperture is my last resort

The aperture/flash ambient/shutter speed rule is most useful when balancing or manipulating ratios outdoors. If you have the power to spare in your studio strobes, you can set them brighter and the f stop/iso smaller/lower. You have to watch the distance to the background with broad light sources such as umbrellas. (there will be more light to bounce around) With a very directional source such as a snoot or grid, it's a lot easier to get the flash/camera exposure in a completely different realm than the indoor ambient light without a lot of spill.


So, as others have said, first thing, set max sync. second thing iso low power high on the light, (the power of your hotshoe flash may be a limiting factor here) The softbox is sort of the middle in terms of directionality. As has been said, take care to angle the light and reflector so that light strikes the subject only. Move the subject/main/reflector away from the wall. Lastly, stop down your aperture and correspondingly increase the output of your flash. (once again, studio strobes even 200ws models are looking better and better here)

Also, it's not cheating to hang a black sheet to tip the balance. If you do all of the things suggested in this thread, it'll be a 90% lighting solution, If you need to change the background from, say a white wall to a white wall with a black sheet... hey whatever works!

so i took alot of the advice here and have gotten good results with blacking out the background, even with my living room lights on! using the grid on my softbox helped quite a bit in controlling spill. ill post pics up in a bit