Background question???

[lildlege1]

Dumb question but asking anyway!!
How does everyone get a nice looking black/ dark background??

 

[mrpink]

Dumb question but asking anyway!!
How does everyone get a nice looking black/ dark background??

Either you kill the ambient light with shutter speed and flash your subject or you use a black backdrop. I have a 6ft x 10ft piece of black polyester fabric for mine- works great, never wrinkles or picks up lint balls.

The first way takes a lot of practice and know how... the second takes a trip to a fabric store.







p!nK

 

[BuS_RiDeR]

Place a black sheet/paper as your BG. Place your subject 4-6 feet away from the BG...

For my last post... Washburn AB5AN, I had to do a little work in Gimp as my backdrop wasa bit dusty...

 

[lildlege1]

Thanks a bunch you guys :thumbup:

 

[Big Mike]

Using a black (fabric etc) backdrop is helpful, but really, you could have a white wall as your background, and if you can control the light properly, you could photograph it as black.

The key is to ensure that the background is darker than your subject, and obviously set your exposure for the subject, not the background. You will want the background to be at least two stops lower/darker than your subject.

With most studio type photography, you will probably want to light part/most of the front of your subject (so they show up in the photo). But this likely means that the light you have pointing at your subject, is also pointing at the background. So the trick here is to have your subject (and thus the light) farther away from the background.

Most things are characterized with at least some diffuse reflection, and when this is the case, you can use the inverse square law to help you out. The law states that the brightness of the reflected light is inversely proportional to the distance from the source. In other words, if your subject is 2 feet from the light and the background is 4 feet, the background will reflect 1/4 as much light. (2 times the distance, 2 squared is 4). If the subject is 2 feet and the background is 6 feet, the difference is 9 times (3 squared is 9).

So by placing your light close to your subject, but far from the background, you should be able to get a dark/black background.

Another key is to constrain the light, keeping it off the background. This is hard with umbrellas because they bounce the light all over. A softbox, on the other hand, directs all it's light in one direction. You can also use something to 'go between' (GoBo) the light and the background.

 

[arcooke]

Using a black (fabric etc) backdrop is helpful, but really, you could have a white wall as your background, and if you can control the light properly, you could photograph it as black.

The key is to ensure that the background is darker than your subject, and obviously set your exposure for the subject, not the background. You will want the background to be at least two stops lower/darker than your subject.

With most studio type photography, you will probably want to light part/most of the front of your subject (so they show up in the photo). But this likely means that the light you have pointing at your subject, is also pointing at the background. So the trick here is to have your subject (and thus the light) farther away from the background.

Most things are characterized with at least some diffuse reflection, and when this is the case, you can use the inverse square law to help you out. The law states that the brightness of the reflected light is inversely proportional to the distance from the source. In other words, if your subject is 2 feet from the light and the background is 4 feet, the background will reflect 1/4 as much light. (2 times the distance, 2 squared is 4). If the subject is 2 feet and the background is 6 feet, the difference is 9 times (3 squared is 9).

So by placing your light close to your subject, but far from the background, you should be able to get a dark/black background.

Another key is to constrain the light, keeping it off the background. This is hard with umbrellas because they bounce the light all over. A softbox, on the other hand, directs all it's light in one direction. You can also use something to 'go between' (GoBo) the light and the background.

Great reply.. I was wondering what the trick to this was as well. Being fairly new myself.. can you elaborate a bit more on this part:

"and obviously set your exposure for the subject"

Is there a camera setting you need to use to achieve this, or do you just mean to keep the subject in mind, not the background, when setting your exposure?

 

[Big Mike]

That brings us to the issue of metering. So when I say 'set your exposure for the subject'...one way to do that, is to meter the subject (and only the subject) rather than the whole scene. One way to do that, is to use centre/spot metering, rather than matrix/evaluative.

If your background is dark enough (darker than the subject), it should be fairly obvious if you have your exposure set for the background or the subject. Take a test shot, if the subject is too bright and the background looks grey, rather than black, then you have too much exposure. Turn down the exposure (shutter speed/aperture/ISO) and shoot again. You want to get to the point where your subject looks good, and if you have controlled your light properly, the background should be dark (or however you want it). If it's not, then change your set up (move farther away from the background etc.) and try again.

 

[arcooke]

That brings us to the issue of metering. So when I say 'set your exposure for the subject'...one way to do that, is to meter the subject (and only the subject) rather than the whole scene. One way to do that, is to use centre/spot metering, rather than matrix/evaluative.

If your background is dark enough (darker than the subject), it should be fairly obvious if you have your exposure set for the background or the subject. Take a test shot, if the subject is too bright and the background looks grey, rather than black, then you have too much exposure. Turn down the exposure (shutter speed/aperture/ISO) and shoot again. You want to get to the point where your subject looks good, and if you have controlled your light properly, the background should be dark (or however you want it). If it's not, then change your set up (move farther away from the background etc.) and try again.

Thanks! I completely get that now.. I forgot about the spot metering.

 

[GrantH]

Mind if I give an example?

In this picture (granted the picture may not be to everyones quality liking...) I spot metered the spot light on the lower right side so that 1)it didn't blow out the bright lights themselves, or if they did...it wasn't a large portion, and 2)so the rest of the photo would be dark, accentuating the lights and lit up portions I was after.