Comparing Different Types of Continuous Light
We will show you different types of continuous light and explain their advantages and disadvantages. In our other article you can also read more about the advantages of continuous light in comparison to flash units and what you should keep in mind when buying one.
There are differences in the design and the use of the light source when it comes to continuous lighting. Halogen luminaires, HMI luminaires and LEDs are mainly used as lighting. These differ in their brightness, colour temperature, light diffusion/range, dimmability and how much heat they generate.
Halogen Lights
Halogen lights or continuous halogen lamps are widely used and for photography beginners they are a cheaper option if you would like to have continuous light. They provide a bright light and they are also very stable and offer a high degree of flexibility thanks to the twistable brackets. Halogen lights provide a rather warm light tone, which are several thousand Kelvin below the value of daylight. The value for daylight is around 5777 Kelvin. However, this can be relatively well controlled by using RAW recording and white balance.
One disadvantage of halogen lights is that they generate a lot of heat. Therefore, when buying a halogen light make sure that the housing has plastic handles. Without any handles or a plastic housing that insulates the heat, you will no longer be able to reposition the light after a certain period of time. Furthermore, due to the heat being generated it is important to ensure that the spotlights are not placed on a highly flammable floor covering, such as a carpet or near highly flammable objects.
Construction spotlights also come under halogen lights. There is a wide range available and they are usually cheaper. Often the cheaper models do not have suitable handles and are very inflexible when using diffusers or foil due to the lack of holes and fittings. Nevertheless, there are also high-quality models, which are suitable for continuous light use indoors.
HMI Lights
The abbreviation HMI means metal halide lamp. An HMI light provides daylight and is mainly used in television and film studios. HMI lights have a lot of advantages. They do not flicker, generate less heat and offer a very bright light intensity. They are also better insulated and they have a bright light. They don’t use as much electricity in comparison to halogen spotlights.
You also have the option of mixing artificial light with daylight, as they have a value of 6500 Kelvin, which is higher than the value of daylight. The light sources remain very stable in terms of light temperature throughout their lifespan. The lighting effect can also be assessed well before the picture is taken. However, HMI lights need a few minutes after you have switched them on to get the desired light colour.
The disadvantages of these types of lights are they are quite expensive and if you use them frequently they will have a shorter lifespan.
Dauerlicht-Leuchten mit LEDs
LED lights as continuous light in photography are still relatively new in contrast to the other alternatives. The newer models are known to be quite high quality.
LED lights do not flicker and you can adjust them more easily. This technology is also easy to handle for non-professionals. A great advantage of LEDs is their mobility because these continuous lights are also available in relatively small, handy sizes that can also be operated with a rechargeable battery. This is a feature that neither the halogen nor the HMI lights can offer. Both types of lighting also need a power source which means that they cannot be used everywhere.
Bicolour LEDs allow you to switch continuously between daylight and artificial light. Some of the lights are even dimmable.
LED lights are gradually becoming more and more available as larger surface lights. As a result, they can already produce lighting for a wide area and diffuse light without any problems. The newer models already provide a soft light and diffuse shadows and in some cases you won’t even need to use a softbox or an umbrella.
Another positive aspect is that a LED light produces little heat, which means that filter materials such as fabric, paper and foils can be used without any issues. In addition to the already mentioned settings, some models offer selectable colour bands within a colour spectrum of 3000 to 6000 Kelvin. This makes it easier to regulate a wide variety of lighting moods indoors. Thanks to the adjustability of the colour temperature effect, you can get good results with great effort with other continuous lights or a flash.
LED lights also have disadvantages. On the one hand, there is a high edge drop outside the core area of the light, which can also be used intentionally as an effect and the use of LED lights is limited to shorter distances.
An LED light generally does not use a lot of electricity, but quite often you will need several of them to light up an area, which can then increase your electricity consumption in comparison to other types of continuous lights. As versatile as a LED light is a lot of models do not shine as brightly as an HMI light. Another major problem is the inhomogeneous colour spectrum of a single coloured LED, which does not produce a clean white light. This is why bicolour technology is needed for studio photography, where two existing white tones can be mixed manually.
Furthermore, it is difficult to illuminate large areas with LEDs because the beam angle of LEDs without a diffuser is relatively small. Especially with smaller LEDs as the light can be very harsh without the use of a diffuser and even with a diffuser it is usually harsher than when using a flash. The light efficiency is also lower than other continuous lights, which means that the LEDs have to be placed very close to the lens. However, this hardly affects the photographer, as the LEDs only generate a small amount of heat.
There isn’t much price difference in comparison to professional halogen floodlights. The lifespan on the other hand is significantly longer and the maintenance costs are lower.
Photographer Chris Gonz from Plauen in Germany also uses LED lights for his work and he explains why: "I do a lot of portrait photography where I sometimes can't use flash, for example, in public spaces, bars and clubs. Here I like to use LED panels, preferably battery powered. Their lightweight design makes them very handy and extremely practical. Also, the colour temperature of many models can be adjusted, which makes it easy to adapt them to the ambient light. The directional effect of continuous light is particularly easy for beginners, as it is easier to see how the light falls onto the subject and thus have perfect control over the subsequent image. Furthermore, the panels are also suitable for short video sequences."
Conclusion
Each light source offers both advantages and disadvantages. The halogen light has an orange light and it produces a lot of heat, which is a disadvantage. An HMI light is quite impressive thanks to its light quality, whereas a LED light is a great choice as it is easy to adjust and transport. LEDs also have a good lifespan in comparison to an HMI light.
