Portraits with Two Lights: Adding a Fill Light

A second mild supply — often referred to as a fill mild or fill flash — can drastically enhance portrait lighting. It reduces the depth of shadows and softens the looks of facial options, amongst other traits. Best of all, a fill mild is straightforward to create: either a simple on-camera flash or a reflector is usually adequate. Nevertheless, a second mild supply can simply as easily hurt portraits. This tutorial subsequently focuses on the way to management the situation and depth of the fill mild in an effort to produce a desired portrait appearance.

harsh overhead sunlight portrait

overhead sunlight portrait with a fill flash

Should you haven’t executed so already, also take a take a look at the primary part of this tutorial:
Introduction to Portrait Lighting: One Light Supply


With a single mild source, crucial issues have been its path and obvious measurement. Whereas these have the same impact with a second mild, they aren’t sometimes assorted unbiased of the primary mild. As an alternative, what’s often adjusted is the relative illumination of the secondary mild compared to the primary mild. This controls how a lot the second mild will “fill in” the shadows from the primary mild, and is why a secondary mild is often referred to as the fill mild or fill flash:

diagram: harsh overhead sunlight portrait

diagram: overhead sunlight with a fill flash

observe: diagrams present the effect of a fill mild, not essentially its excellent position (extra on this later)

Perhaps the most typical lighting state of affairs is to make use of an on-camera flash as the fill mild, and daylight as the primary mild. One might additionally use a secondary flash as a fill mild within the studio, or might even use ambient mild because the fill mild and as an alternative have the flash be the primary mild. There are lots of prospects. The secret is figuring out how you can control the qualities of your fill mild — regardless of what supply is getting used to create it.


The phrases “flash ratio” and “fill light ratio” describe* the relative quantity of sunshine from the primary and secondary mild sources, and effectively decide the overall distinction. For example, a worth of 1:four signifies that the fill mild is a quarter the depth of the primary mild. Extra balanced ratios produce weaker shadows:

no fill lightFill Light Ratios:


no fill mild

weak fill light1:8 – 1:2

weaker fill mild

strong fill light1:2 – 1:1

stronger fill mild

comparison of different fill light ratios
Select a Fill Light Ratio:

Portraiture sometimes seems better with a flash ratio near 1:2. That is robust enough to supply delicate shadows, but not so robust that it eliminates shadows totally (inflicting the topic to be seem flat).

Nevertheless, one ought to all the time be cautious of such seemingly strict rules in images. Much less fill mild is usually used for darkish, “low key” fashion portraits with well-defined shadows. Similarly, extra fill mild could be essential to render a brighter “high key” type, or just to offer a softer look (similar to with a photograph of a child). When unsure though, the 1:2 ratio is a protected start line.

*Notice: These phrases could be a little confusing, as a result of a “fill light ratio” refers to the ratio between the secondary and first sources of light, whereas the “flash ratio” refers back to the ratio between the sunshine from the flash and ambient mild. To make issues worse, typically the ratio is used to describe the ratio between complete mild (ambient+flash) and that from flash alone. The numbers are typically also reversed, but the smaller quantity all the time refers back to the fill mild. We’ll persist with the same definition throughout this tutorial, and since we’ll only talk about situations the place flash is weaker than different mild sources, each terms are synonymous.


In contrast to the primary mild supply, the only location for a fill mild is near the digital camera’s line of sight (“on-axis”), but not so close that it appears in your image. That method, any shadows forged by the fill mild gained’t be seen from the digital camera’s perspective, so it gained’t matter if these seem onerous (resulting from a small supply). Perhaps the simplest approach to obtain this kind of fill mild is to make use of a built-in or on-camera flash.

on-camera fill flashOn-Axis Fill Light
(shadows fall behind the topic)
off-camera fill flashOff-Axis Fill Light
(shadows fall throughout the subject)

However, an on-axis fill mild could be too proscribing, and has a greater probability of manufacturing direct reflections off the topic. Many subsequently use a fill mild which strikes their subject from a path which partially opposes the primary mild (“off-axis”). This targets foremost mild shadows more efficiently — even when the fill mild ratio remains unchanged — and is subsequently additionally much less more likely to affect the overall exposure.

off-axis versus on-axis fill light
lighting diagram of off-axis vs on-axis fill lights

a Fill Light:Off-Axis

The sq. mild represents the primary mild, and the octagonal disc represents the fill mild.
Above example uses a 1:1 fill ratio as a way to improve visibility of fill shadows.

Nevertheless, off-axis fill has its own disadvantages, with maybe the worst being that one now has to fret concerning the look of shadows from the fill mild. If these aren’t made sufficiently smooth, they will cause unrealistic-looking double shadows. To counteract this, the farther a fill mild is placed from the digital camera’s line of sight, the larger that mild source must be. Move your mouse over the alternatives above to see this effect.

Observe the second shadow to the suitable of her nostril with the “off-axis hard” fill lighting. Also word how the on-axis fill mild avoids producing double shadows despite the fact that it is a small (arduous) source, however that it doesn’t remove the shadows as completely (regardless that it uses the same 1:1 fill mild ratio).

Additionally remember that off-axis fill lighting requires a extra complicated lighting arrangement, and is subsequently often reserved for portraits in a studio. An off-axis fill mild also technically isn’t a true fill mild, since it can’t lighten all shadows visible to the digital camera — simply these from its path. For instance, within the above portrait, the off-axis mild is unable to scale back the shadows behind the hair on the higher right.


camera force flash icon

Many only use flash when their scene has insufficient mild for a hand-held photograph, but doing so misses out on maybe an much more helpful perform: fill flash. Though it might sound counter-intuitive, portrait flash is probably most helpful when there’s plenty of daylight. Thankfully, most cameras default to using their flash as a fill flash when the subject is well-lit* — but provided that you pressure the flash to fireside.

Cameras often default to a flash ratio near 1:1, however this may be substantially off because it depends on your digital camera’s metering system. To fine-tune this ratio, you’ll need to apply flash publicity compensation (FEC). This modifies the quantity of flash that your digital camera would in any other case emit, while leaving the opposite exposure settings unchanged.

*Observe: Properly-lit signifies that your digital camera doesn’t deem digital camera shake to be a menace, which often interprets into having an publicity time that’s shorter than about 1/60 of a second.


Other necessary fill mild methods and issues embrace:

Natural Fill Lighting. Up to now we’ve targeted on situations where pure mild is the primary mild source, and the digital camera’s flash is used because the fill mild. Nevertheless, these roles might easily be reversed. The supply of pure mild often must be tender although, comparable to from an overcast day or a subject within the shade. One additionally sometimes needs an off-camera or bounced flash in order for this to supply optimal outcomes (see the discussion about lighting path within the tutorial on portrait lighting).


Reflectors. These make a single mild supply illuminate a subject from a second path. The reflection is dimmer than the primary mild, so reflectors are most commonly used as a fill mild. An additional advantage is that this mild can simply have the same white stability as the primary mild, if desired. Nevertheless, a disadvantage is that reflectors typically don’t provide enough mild (even for a fill mild). That is extremely depending on the reflectivity of the fabric, in addition to its distance from the subject. To increase illumination, reflectors are subsequently often positioned as near the subject as potential — typically just outdoors the picture frame.

Subject-Background Separation. With natural mild portraits, a fill flash may also help create further subject-background separation, because the flash is probably going to offer a lot more illumination to the (nearer) subject than the (farther) background. You possibly can management the power of this impact by (i) shifting nearer to your subject and/or (ii) shifting your subject farther from the background.

high contrast portrait with low ambient light

low ambient mild

Ambient Light. All scenes have some quantity of fill mild — no matter whether this has been added deliberately. Light from the primary source bounces off partitions and other objects, which collectively acts as a fill mild. Shadows are subsequently never absolutely black, and the actual quantity of fill mild is often a little larger than that offered by your fill flash. Nevertheless, studio lighting can nonetheless achieve very excessive distinction.


General, an important fill mild decisions are:

  • Location: whether or not to put the fill close to your digital camera’s line of sight (on-axis), or off to the aspect (off-axis). On-axis fill is simpler since one doesn’t have to fret about how shadows appear, but off-axis fill provides extra flexibility with placement and management over the appearance of reflections.
  • Fill Ratio: the relative power of your fill mild, as compared to the primary mild. A great start line is usually one half fill mild for every two elements important mild (denoted as a 1:2 ratio), but this may even depend upon where your fill mild has been situated.

For background studying on this matter, also see part 1 of this tutorial:
Introduction to Portrait Lighting: One Light Source

For other comparable subjects, additionally go to the next tutorials: