The Perfect Backlight pt 1
You can read any number of articles or watch hours of tutorial videos on backlight, (hair light, a kicker, whatever you want to call it) but few actually show you a solid method on how to properly get one set up, while considering all of the important factors.
Art model Dakota Snow came by the studio to help us demonstrate this very simple yet, evasive theory, in a two-part post.
In the image above, the lack of backlight is used to blend the model into the background. While it works well for an anonymous fine art image, this is the opposite effect of what is typically desired for a portrait... or is it?
In part one, we are going to talk about WHEN we want to use a backlight, and selecting the best modifier for the situation.
When is a backlight necessary?
The most common function of a hair / back light is to create separation between the subject and the background. This occurs in many situations, such as when the subject and background have:
- similar colors
- conflicting patterns
- similar exposure values
Even in the situations above, adding a back light to your setup is only one option. Some other methods to create separation are
- Decreasing depth of field
- Using a key or ambient light to adjust exposure
- repositioning your subject
I will only add an extra light to my setup when ABSOLUTELY necessary. I did a similar post (*warning NSFW) with Dakota Snow on creating separation without a backlight! Aiming to be efficient with gear in a studio is good practice, as long as it is not accompanied by a compromise in quality. Besides, you want to spend your studio time shooting, not setting up.
So, if you have come to the conclusion that you want a backlight, there should also be a significant amount of consideration into what modifier you should choose.
Selecting the 'best' modifier
I know this may sound overtly obvious, but I promise there is more to it than it seems. Keep reading, because this should not be an arbitrary decision.
Your frame is the determining factor. Is this a medium portrait, or full body? Will the subject be standing or sitting? Understanding HOW MUCH of your subject will need to be actually reached by your backlight is the FIRST step in choosing an appropriate modifier.
In this case, our model is standing, and we are taking her portrait. This means that we only need light on a very small area, her head and shoulders.
The obvious choices are the smallest soft boxes possible. In Studio-B, that is the 28” Deep-Octabox, or the 3’ Baby Stripbox.
Small (28") Deep-Octabox
The Deep-Octabox has a fabric egg-crate grid available that will help control spill and make its output is a tightly controlled cone of light. In many cases this is a great choice as a backlight, but there is still one that is even better for this application.
We chose a very small soft box made by Paul C Buff. This handy little piece of gear is only 9 inches by 3 feet. The studio staff calls it the ‘baby’ strip box, and I believe that it is the smallest softbox made for Alien Bees strobes. The baby strip box is a permanent piece of gear that you can always count on being in Studio B.
There were many more options available, but this modifier was the best ‘fit’ for a few reasons
Small size makes it easy to boom Deep outer lip and fabric (egg crate) grid control light spill Width (when sideways) is perfect for covering shoulders Soft, double diffused light with subtle falloff
The Background Reflector
The background reflector, also by Paul C .Buff is a viable option but is typically better suited for lighting an actual backdrop like a wall, fabric, or seamless paper. It can serve a purpose as a backlight in a pinch, but the modifier’s shape requires it to either be directly behind your subject (using the subject to hide the light and stand) , or off to one side, which can leave an uneven light on your subject… unless you had two of these to work with.
Yes, you could throw this background reflector onto a boom as well, it is certainly lightweight enough, but again, the shape of the light output makes it extremely difficult to manage spill. Without being properly lined up, this can create lots of lens flares due to it being pointed right at your lens.
Also, remember that this is basically just an angled reflector made of metal that has been painted white. Because there is not much diffusion happening before it leaves this modifier, the light output will be hard, with a very fast fall off. That quality of light is not what most people desire as an accent or hairlight because it seems ‘harsh.’
Large Strip Box
Nearly identical to the baby strip box in Studio B, there is a larger strip box available in Studio A.
The Chimera branded modifier has the same deep lip to control light spill, and the same dual layers of diffusion (inner and outer baffles), the noticeable difference is in the dimensions. This large strip box is 18 inches by 4 feet; so it is far better suited for situations where you need coverage on a subject that requires more vertical clearance, or multiple subjects when used horizontally.
A much bigger, beefier, boom stand would be required to fly this piece of equipment, its not likely that this would be the best option except for a few rare scenarios. The studio does own a Manfrotto boom stand that can handle this load, but it is in storage because it takes up too large of a footprint. In Studio A, the gridded reflector is a much better choice.
The same 7-inch metal reflector that is included with most monolight studio strobes makes for a very useful backlight tool. When used alone, it provides a hard, unmodified light that has simply been directed ‘forward’; but when used with a grid, the light has a much tighter pattern that is easier to control and has virtually no spill.
The beehive pattered, metal discs just snap-in. The Baltimore studio spaces each have a set. The grids come in a compliment of degrees from 10 to 40. The lower number equals the tighter angle of light allowed. The higher the number, the wider the cone of light.
These are great because the light pattern escaping is so narrow, that you can put it where you want, and not worry about it hitting your lens. Like most other modifiers, this is easier to keep out of the way when placed on a boom stand.
This is just a summary of the modifier options that are best suited to use as a backlight AND are available to you when shooting in our Baltimore studios. This list is certainly not all inclusive, and it doesn’t mean that you can’t use a beauty dish as a backlight. Maybe you want a lens flare!
Window light can also make for a fantastic backlight. When exposed properly, strong rays of sunshine will make light colored hair really shine, and separate darker colors from the background. Don’t be shy to experiment with your light, it’s the best way to learn!