This is a guide covering subtractive lighting.
In this glossary definition you’ll learn about:
- Subtractive lighting definition
- Purpose of subtractive lighting
- How to use subtractive lighting
- What to use for subtractive lighting
- When to use subtractive lighting
- And more
Sometimes you will only notice the importance of an element in your photography when it’s not there. In some cases, it’s the properties, extra lighting, or in this case the shadows.
Let’s dive in.
What is Subtractive Lighting?
At its core, subtractive lighting is the act of removing light. Essentially creating shadows to produce a more dimensional image. Too much light on your image would poorly affect your image, most likely making it look flat.
As responsible photographers, we should make our photos look three-dimensional although they may be in two-dimensional media.
This means that we need to create shadows, even when there are none.
There are times when you want your image to fit a certain mood, either heartwarming, dramatic, serious, friendly, calm etc. To properly create this mood, photographers need contrast to create deep shadows in their images.
You can create these situations using natural light, but a studio will do a better job at this. Studios will ensure your contrast is sufficient for your needs.
What is the Purpose of Subtractive Lighting?
The purpose already lies in the subtractive lighting definition, to create great shadows, reducing the light into more proper size, or preventing light to shine on a particular area.
Let’s say that you already have the perfect light for your catchlights in the eye, but as a consequence your subject’s face becomes flat. This means that either your light source lacks direction, is too large, or both.
This is when photographers use their tools or surroundings to create shadows. The light-blocking tool will be placed around the area where the shadow should be seen.
The shadow will improve your final image and make it more three-dimensional.
Depending on the situation, you’ll probably need different tools too. A black-colored device can block light from a light source.
Unfortunately, it tends to suck the light from its surrounding areas. On the other hand, white-colored devices can bounce the light around your subject, transforming the lighting around them.
Photographers tend to use light reflectors on areas that already reflect light, such as light-colored concrete, buildings, or inside a white interior.
The act of reducing the lighting and adding shadows to your subject will also create a different ambiance.
Depending on the amount of light blocked, your subject can look like “someone resting under a tree on a sunny day” to someone standing under the sun at high noon. It changes people’s perception of the image and also the image’s whole meaning.
How to Use Subtractive Lighting?
Let’s start with the basic decisions that surround subtractive lighting. Photographers will often ask you to, first of all, search for a main source of light and a fitting background based on that light.
Sadly, this strategy will only work if you shoot at the perfect time of day with the ideal light. For the other photographers, they will usually start from an optimal background, then optimally use the available lighting.
The method above gives you much more flexibility if you decide to change the lighting on your subject, rather than the other way around.
With the background and its lighting secured, it’s time to decide to either add or subtract the light sources. Some rare situations may need you to utilize both, but it will commonly become a straightforward decision.
If the background lighting is more intense than your subject, consider adding the light sources. On the other hand, if the lighting in the background and subject is the same, consider subtracting the light.
One of the easiest ways to learn subtractive lighting is by practicing. Gradually start from a subject with the available light and slowly observe the changes as you add or subtract the light.
Maybe use a white-colored object to fill the unflattering shadows around the eyes, jaws, and nose. Adding another source of light to add a flattering catchlight to the subject’s eyes. Observe and try to fix areas that you can improve, maybe some shadows could help define your subject features while making the image more dramatic?
You can use your gobo to create an area that transitions from the highlights to shadows. Such techniques are able to make the subject’s face more noticeable, while also making them appear thinner.
Depending on your understanding of lighting and portrait, the changes that you can change are almost limitless. Keep transforming your image until it looks more interesting and matches the likings of the client and yourself.
What to Use for Subtractive Lighting?
The most common tools used for blocking unwanted lighting are gobos, some people also call them flags. Although these terms have existed since long ago, people rarely use these tools today.
The flag is black, opaque, flat, and can typically be held by your hand or mount. Most of the time, people will always use this flag in locations that are too open and produce flat lighting.
Don’t have a flag? Then use your surroundings instead! Similar results can be achieved by using a smaller yet natural light blocker, such as a tree.
The generic term of gobo itself is “go-between” which, as you know can be anything that goes between your subject and light. Your gobo can be the man-made architecture that is available around your location too!
Gobos can start from buildings, houses, porches, trees, hedges, pretty much anything that fits in the term gobo.
If it blocks light, it’s technically a gobo, even if it’s just your hand. Each gobo has its own advantages and disadvantages. Trees can help you block the light while also looking good in the picture.
Photographing outside your studio can be quite a hassle with all of the light coming from multiple directions and reflected by various objects.
Subjects in the open will most likely have strong lights coming from both sides of the face. The photography industry refers to this as flat light and looks pretty bland.
This flat lighting can be counteracted by using the previously mentioned flag. These light, yet large flags/gobos can easily block light that would otherwise create flat lighting on your subject.
The blocked light will then create a flattering three-dimensional aspect of your image. You can block the natural light from wherever you want, some situations will require you to block the backlight, or maybe some light that would otherwise reflect on their face.
When to Use Subtractive Lighting
Optimally, you would use subtractive lighting when your image looks rather flat. You are then given the artistic opportunity to either subtract the light on the background or face.
If you decide to use the gobo on the background, you will separate the subject from the background. Making it look more three-dimensional.
However, if you choose to subtract the light on the face you will make the short lighting effect. You can recreate short lighting by positioning the face of the subject (which is covered by the gobo) closer to the camera. Photographers will often use the natural type of gobo since they can also incorporate it into the picture.
Maybe use a canopy or tree, as long as it doesn’t fully block your main source of light and eliminates the background bokeh.
Bokeh can be a smart tool to further separate your subject from the background, further emphasizing them as the center of attention. This method would most likely be your approach to individual portraits.
On the other hand, there are also group portraits. They are probably the most difficult to do, but they are always worth the effort. Since small trees and flags are unable to block light for large groups of people, you’ll need to put more effort into scouting your location.
Keep your eyes peeled for large trees, buildings, or hedges. They can potentially serve as the gobo and help add a three-dimensional effect.
You may need your group to be a bit closer to the gobo, why? Because you need to see how effective the shadows are on your subject’s face. Some photographers will run into difficulties when looking for this subtle difference with their naked eye.
I suggest using a light meter to measure the highlight on the subject’s faces and take a test photo afterward.
Light meters will make the highlights and shadows pretty obvious if compared to when viewing the camera’s rear screen. Check the shadows and how effective they are. But which subject should you measure with a light meter?
Well, perhaps the subject that is closest to the gobo, between 20 to 10 feet depending on the size of your gobo.
Oh, for a little side note. Please don’t stress it too much if you’re unable to find the best location possible for your subtractive lighting, you’ll never always find it. It is perfectly okay to use the softer kind of flat lighting when making a group portrait. But make sure to have the other elements in check.
Keep your groups in the shade and let the main source of light shine on your background. The usage of purely natural light with a little tampering using a subtractive light technique will result in flattering portraits.
They will look absolutely more natural than most flash techniques. In addition, you can also save money since you don’t need to purchase additional equipment such as; Speedlights, soft-boxes, etc.
Instead, you can save your money on a high-quality portrait lens. Isn’t that just nice?
I hope your question of “what is subtractive lighting” has been answered with this article. It’s basically adding shadows using objects that block the light between the light source and your subject.
There are many options available to you depending on your knowledge of lighting and portrait photography.
Photographers mostly use subtractive lighting to salvage images at locations that are too bright/flat. The shadows add definition, hide non-essential features, make your subject’s face thinner, and also adds a sense of drama depending on how you use it.
The easiest way to get used to it is by learning and observing the changes that occur while fiddling with the light using your “gobo.” Good luck and have fun!