Invisible Black Backgounds

SkvLTD

SkvLTD

Senior Member
Only real issue I can see is trying to do anything more than a portrait/bust (in that contrasty style)- it would take A LOT of lights and a LOT of snoots.
 
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wornish

Senior Member
Watched the video but don't understand the point. Have I missed something?
are you supposed to take the second shot as a second exposure on top of the first all black one ?
if not what's the point ?
 
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Felisek

Senior Member
wornish said:
Watched the video but don't understand the point. Have I missed something?
are you supposed to take the second shot as a second exposure on top of the first all black one ?
if not what's the point ?
Click to expand...

The first shot (without the flash) is a demonstration that the ambient light is so underexposed (in manual setting 1/250 s and f/16) that it creates the black image. Then, we turn the flash on and take another shot. Background is not affected by the flash, as it is not illuminated, so it stays black. But our subject is illuminated and if the flash is powerful enough, it will create enough light to have a portrait against the black background.
 
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WayneF

Senior Member
The flash has to be powerful enough to exceed the daylight. Larger studio lights are frequently used outdoors. This will be easier indoors. The flash will have normal (much more) range and versatility if it does not have to overpower the sun (or even a gray day), to be seen. If the background is made black, there is no reason not to do it indoors. One difference though is that outdoors can have a more distant background (to avoid being lighted), and note the flash is not aimed at the background. An actual black background indoors can help a lot.
 
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Lawrence

Senior Member
siamthai1 said:
Show us the result
Click to expand...

Sure.

Note how sharp the entire black background is - I guess because of the high (narrow) aperture. :)

Black background.jpg

In all seriousness this was an awesome "Ah ha!" moment for me whereby I realised that mistakes should be viewed as a learning curve as in:
"OK what did I do to get that result, and how can I apply the same technique to create a different shot? In other words how can this improve my knowledge of photography?"

Just saying ...
 
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thequeenscheese

Senior Member
I was playing with this yesterday but I found out that my d5300 doesn't have auto fp, and the max sync speed with built in flash is 1/200 so it makes this not possible, are there any other routes for it?

In my case essentially for portraits just to achieve the black background like you can see in arty macros etc?
 
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WayneF

Senior Member
thequeenscheese said:
I was playing with this yesterday but I found out that my d5300 doesn't have auto fp, and the max sync speed with built in flash is 1/200 so it makes this not possible, are there any other routes for it?

In my case essentially for portraits just to achieve the black background like you can see in arty macros etc?
Click to expand...

But nobodies flash allows more than 1/200 or 1/250 second shutter speed, so that is no issue at all. You're not trying hard enough. :)

It is not hard. A black background generally only depends on these factors:

1. Background sufficiently far back to not be illuminated by the flash added to the foreground. Talking maybe subject at 3 feet and background at maybe 9 feet (3x farther than subject). It helps of course if the background is black, but not required, reduced lighting can make any color look black. Flash falls off with distance, 3x distance is pretty dark back there. 4x is better. Really the idea is that a moving the subject closer to the light makes the same background relatively more distant from that light .... the difference between them.

2. Ambient light sufficiently low so as to Not illuminate the background well enough to be seen. That does NOT mean dark, it just means normal indoor lighting, but Not bright. A white background with no light on it looks black. What helps this greatly is low ISO and stopped down aperture and 1/200 second, to make the ambient light low for the photo ... yet the flash uses enough flash power to overcome it and still have strong effect.

Example, regular studio flash taking regular studio portraits probably uses ISO 100 (a low value) and maybe f/8 (a high value). The main light is probably only about 3 feet from the subject (close is better to create a relatively distant background - also makes the main light appear bigger and softer). The main light probably has a strong incandescent modeling light in it. Yet, even with normal indoor room lighting, ISO 100 and 1/200 second at f/8 is a BLACK picture, with modeling light on the near subject, but without the flash. The modeling light looks bright, and it is a strong orange, but it needs more than ISO 100 1/200 f/8. It does not even show up. The background is black too (without the flash). And the flash at 3 feet lights the subject, but does not reach to the background at say 9 feet (will be 3 stops down back there - and not necessarily even aimed that direction).

So... for a black background, just keep the light off of the background (don't aim main light straight back, instead angle it more sideways to then miss the visible background. If necessary, tape a card on the side of the flash to block and keep the light off of the background... called a barn door). And keep the background fairly far back. Do NOT use high ISO or wide aperture or low shutter speed, which would simply emphasize the ambient. De-emphasize the ambient with low ISO and stopped down aperture and 1/200 second. Use flash power to overcome that for the final near picture.

See this example. 45 degree Portrait Lighting Setup

See about 25% down the page there to the picture that says "Main Light Only". See the black background? See in the top pictures where the background is? The background needs its own light to show up and be visible. This is ISO 200 only because the D300 only goes down to 200. f/10 and 1/200 second.

Try things. If you need a little more, then do a little more.
 
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thequeenscheese

Senior Member
Thanks Wayne that is a nice in depth helpful post, I think maybe I was asking too much with the ambient light I was in and maybe the room I'm in is too small to achieve this also..
 
cwgrizz

cwgrizz

Senior Member
Challenge Team
On a similar vein to this, I read a book on creativity using a single flash. Something that they talked about was making a scene look like it was late in the day (dusk) or stormy by doing about the same thing. Set the camera exposure so the scene is underexposed and then with those manual camera settings, use the flash to illuminate the subject. It appeared to have a dramatic effect on an otherwise bland photo. One of these days, I will try it. Ha!

Disclaimer: I haven't watched the u-tube video yet, but from the comments I think I am on the right track with this post. :loyal:
 
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STM

Senior Member
This will work if you are only using one or at most two lights, but anything more demanding than that and it would be a major headache. But for a single light it does have some promise!
 
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