White Seamless Tutorial :: Part 3 :: From White To Black.
We’ve taken our white seamless BG and made it pure white. The task set before us now is to get a few more visual options out of that white seamless paper or simple white wall we are shooting against.
When I got my first studio space I had few resources to fill it up with backgrounds and stuff that studios should have. The very first thing I bought was a roll of white seamless paper. I had to start using it with two lights. One on the subject and one on the background. That’s all well and good but I needed to have the ability to get as many looks out of that one background. These are some of the simple and effective techniques I still use to get some different looks from a single background.
The first thing you can do is simply turn the background lights off.
The image above is the same exact photo except for the fact that I turned the BG lights off. I shot one with the lights on. Then one with the lights off. Same settings on my main light and same settings on my camera. Your white BG is now a medium grey.
Here is a full length shot with the tile board removed.
I removed the tile board because it can be a bit difficult to get it to blend seamlessly when you are lighting the BG. It can be done you just have to finesse your light and shooting angle to the point where you no longer see the edges of the tile board on the floor and maintain a consistent tone of grey while still picking up a bit of reflection under your subject. Currently I don’t have an example of that on hand. I’ll dig for one in the archives and post it when I wrap this tutorial up.
If you can wrap your head around things like inverse square law and feathering your light then you can begin to make that BG any shade of grey from black to light grey.
Inverse square law is an equation that talks about math stuff about how light falls off over distance. I’m a photographer. I like pictures. I don’t like physics. Inverse square law to me is like that quote about electricity that I’ve heard before… “I don’t know how electricity works but I use it everyday.”
If you double your distance from flash to subject, you lose 75% of the light. To me it seems like if you double distance then you lose half of your light but some dudes and some ladies (probably more dudes than ladies though) figured out that is not the case. You double distance from flash to subject you lose 75% of the light. Not 50%.
In Myth Busters type of science that means when you double distance you lose 2 stops of light. If you double one foot that means you lost two stops of light at the two foot mark. If you double 20 feet… you lose two stops at the 40 foot mark.
Let me say this now though… Before any of you get on here with your Texas Instruments graphing calculators to show me where I’m wrong on this… Take it to DPReview and fight it out there with the other measurebators. I don’t care! Like I said, this is some Myth Busters kind of science explanations.
With a point light source like a straight flash it looks like this…
From f22 to f16 that is 7 inches. From f5.6 to f4 that is 3.5 feet. If your subject was standing where the f22 tick mark on the wall is and the white seamless BG was over there by the 5.6 tick mark then by the time you expose properly for the subject at f22 then your BG would be (16, 11, 8, 5.6) FOUR stops under exposed from your subject.
Here’s the basics that a public school educated guy like me can understand. If you get your subject some distance away (like 10 feet let’s say) from the BG and your light source really close to the subject (like 1 or 2 feet away) then once you properly expose for the subject…. the light falling off toward the BG falls off to the point that your BG can be 2 or 3 stops under exposed from the subject. The more you under expose the BG the darker it gets.
Again… The larger your ratio of exposure is from your subject to BG the darker the BG gets. The smaller the ratio gets, the lighter the BG.
Huh? What? Yeah, I know. It looks like this without any use of Photoshop.
I’m going to post that same photo right after this explanation…
For these two images I kept the subject the same distance from the BG. He was about ten feet from the wall there. For the image on the left the softbox was about 5 feet away from him. Exposure on him was f2 or something. Then I moved it in really really close. Just outside of the frame. Once I closed down my aperture to compensate for the light being much closer to him, the light ratio between his face and the wall was now a larger ratio thus making the BG darker.
Still don’t get it? Reading my explanation over again won’t help much because I think it confuses me as well so let me try to sum it up another way. All you engineers out there are laughing your butts off at me because this stuff is elementary. Like I said, I went to public school.
Get your subject about 10 feet off of a wall and get your light source 7 or 8 feet away from your subject in a position that light is hitting your subject AND your background. Make a proper exposure for the light hitting your subject and look at the white BG. It will be a lighter shade of grey.
Keep your subject right there and more your light in really, really close to your subject. Like one foot away (just outside of your frame). You have now changed the exposure so you are going to have to stop down your aperture until you have a proper exposure on your subject. Once you have the proper exposure on your subject, that white BG will now be a darker shade of grey than image you shot before with the light 7 or 8 feet away.
If you are reading this and don’t get it… Get off your arse and go shoot it. You’ll see it pretty quickly.
You can further eliminate light falling on the BG to get the BG to go darker and darker still until you just “blow it to black” as I like to say. Or, you make dark with light. I typically do this with feathering my light and getting my subject even further away from the background.
When you “feather” a light you are positioning your light in such a way that it isn’t pointing directly at your subject. Instead, it is pointing a little bit away from subject yet not pointed so far away that you are no longer lighting your subject. You are just wanting the subject to catch the feathered edge of light coming out of your modifier. Point that light AWAY from the BG yet still getting some on your subject.
If you tweak your feathered light just right and have a good distance from your BG then you can take that white seamless (or just about any other color of BG) and it will become black.
Here is a four light set.
Two lights on the BG, one light with a grid to light his arm, one light zoomed in to light his face. Here is what it looks like on white…
Remember how I talked about my philosophy in all of this is I light my subject independently from my BG? With my lights on my subject set up properly, those lights aren’t adding any exposure to my BG. So if I turn the BG lights off and just use that tight grid and a zoomed Vivitar 285 I get this…
I did NOT change the white background out for a black one! I pinky promise! I just kept that grid and that zoomed light positioned in a way that none of that light hit the BG. NOTE – I’m staying at my sync speed on my shutter speed to make sure I’m killing any and all ambient light falling on the BG. Shutter speed controls ambient light. Even though there was light in the studio when I was shooting, I was shooting at f8 at 250th of a second or there about so I wasn’t exposing any ambient light in these images with black backgrounds.
For the image above she was about 15 to 16 feet away from the BG. I had a big softbox pointing just in front of her. Enough for the feathered edge to light her. Then I had a second light add a bit of a side light for separation making sure that the side light did not hit the background.
Grid spots are awesome. You can use those things to keep light off of any BG you may be using like this…
Grid spots have a small feathered edge of light. You can point the main circle of light in front of your subject and just get their face into that feathered edge and it looks like this…
You can grid a subject again, add a background light pointing toward your subject and get this…
You can take a big ol’ softbox, move your subject away from the BG as much as possible (like 15 feet or so), under expose the whole thing just a bit and get this…
Take it light grey…
Take it darker…
Set your BG lights to a low power setting and get them evenly positioned on the BG and match the BG exposure with the subject exposure and get a very even tone of grey through an image…
Position your light in just the right spot where you get just a bit of separation from dark shirt or hair to a darker BG…
Keep the light on your subject but OFF of your white BG so that the BG goes black. Then double or triple stack some colored gels on your BG lights and set them to a fairly low power setting and you can now add color to your white BG…
IF you let the clean white light from the subject light hit the BG when you are trying to gel it to a color, then you are going to contaminate that gelled color back there and you’ll lose the saturation of the color you are trying to achieve. I used a grid spot in the image above to keep light just on the subject and off of the BG. I kept him far enough away from the BG that the red light from the BG didn’t wrap around him and give me some funky color shift on the subject.
White. Grey. Black. Red. Blue. Whatever. One background. Many options.
The next tutorial will be about what we can do with some of these images in post production. I’ll show you things I do in 30 to 60 seconds of time that changes things up even more. After that I’ll post a few different lighting techniques for lighting your subject on the white seamless. Then I’ll have a post where I’ll be open to questions in the comment section and I’ll cover the questions already in the comment section now.
Then I’ve got something fun for us after that and that will conclude this tutorial! You can expect for this to be all wrapped up this month. My schedule is a bit hectic right now.
ETA – If you have questions about any of this, drop them in the comment section here on Part 5 of the tutorial. I will be following up on this tutorial with a new post answering all the questions at once.