Constant or pulsed light in photography

Permanent sources

A permanent source is defined as one whose light is emitted over a long period of time, from on to off. Such sources can include daylight, incandescent lamp, spotlight, flashlight, and so on. As you can see from the list such sources can be divided into natural and artificial, between which there are some differences.

Everyone is likely to have taken his first picture with a permanent source – outdoors or indoors. Permanent light is more accessible than pulsed light. Although permanent light is familiar, there are still peculiarities for photography.

Features of a constant light source

Among the features that go along with working are distinguished:

Operation by adjusting the shutter speed or ISO. You can’t control the power of the light output (not counting studio conditions). The camera captures as much light as the source emits. In the case of a lack of light, you have to be content with increasing the camera’s shutter time or increasing the light sensitivity, assuming a constant aperture, unable to change it for reasons of photographic idea;
Photographing with constant light allows you to press the shutter button at any time without the fear that the light will not work at that time. This is what happens when you use a flash. This type of lighting does not have that disadvantage;
The ability to see the frame before you release the shutter. Preview is a big plus of permanent lighting. The photographer can plan the light and shade pattern and adjust shooting parameters without taking test photos, because the result is visible on the screen all the time;
Natural permanent light as well as artificial street light does not require the photographer to have power sources. The sun or street lights shine no matter if you have batteries in your pocket;
Mixing or abrupt changes in constant light can affect the white balance settings, you have to be careful with these.

The above features are both advantages and disadvantages. That said, the same feature can be both a plus and a minus, depending on the challenges the photographer faces.

Scope of a permanent light source

Despite its limitations and disadvantages, permanent light is something we live with. That’s why the scope of this kind of lighting is all genres of photography, much less video. There are cases where it is preferable to use pulsed light, but even then permanent light can be used and help achieve the desired results.

Constant light is most often used when you can control the shutter speed without affecting the idea of the photograph. Then all kinds of results are achievable. Those are, of course, landscapes, subjects, interiors and still life. The night landscape is also attractive because of the constant light and shutter speed.

Impulse sources

The second type of photographer’s light is pulsed light. As the name suggests, the distinguishing feature of such lighting is the use of a pulse. The pulse is short-lived but powerful. Given that most shutter speeds are also relatively short-lived, the flash pulse is enough to illuminate the frame. Its high power allows you to use ultra-short shutter speeds (up to 1/500) and get the desired results.

The flash source is based on a capacitor that stores energy from the battery and then outputs it as a powerful flash of the lamp. Hence some peculiarities of using pulsed light sources.

The features of a pulsed light source

The peculiarities of pulsed light are explained by its artificial origin. With the nuances of work when using this type has to be reckoned with. Undoubtedly, the differences of such lighting from the permanent entails its own pluses and minuses:

It takes time to charge the capacitor. It may only take a second, but it can be worth a lot. Missing a shot at the right moment because the flash is overcharged is not uncommon;
The inability to use continuous shooting. A pulse source simply will not have time to recharge;
The minimum shutter speed is limited. The so-called sync shutter speed is the shutter speed at which the shutter curtains will not be caught in the frame. Often this value is 1/200 second, which depends on the model of camera. There are options with a sync shutter speed of 1/250. There is also high-speed sync. In short, this parameter requires consideration when using and is a distinctive feature of a pulse device;
When using a pulsed light, there are the concepts of first-curtain sync and second-curtain sync. Using one or the other brings different results;
Pulsed light equipment needs a power source. This can be batteries or mains power. But there is no naturally occurring pulse source (unless lightning, which is not feasible in practice).

Scope of a pulsed light source

More often than not, pulsed light units are used for portrait photography in the studio. Also, the use of on-camera flashes is useful for reportage photography indoors. It is in these two genres of photography pulse lighting equipment occurs most often. But this does not preclude its use in any other areas. The areas of application always depend on the benefits, so the studio, where controlling the light flow is important, and reportage, where you need to have enough light for clarity and quality, are the main areas of use of pulsed lighting devices.

It becomes clear that from getting to know the camera, it is important for the novice photographer to quickly move on to learning about lighting. Light is the head of the photography business, and there are only two types. That’s not a lot to learn about them. Now you know whether constant or pulsed light is better to use in photography, depending on the direction of your development in photography. It is important to understand that these sources can be interchangeable if necessary, because the availability of light of any origin is better than the lack of it.