How and when to use Emissive Materials in Sketchup

By using emissive materials in your SketchUp projects you can create the perfect lighting. The emissive materials are different than artificial light and can help you create effects which cannot be achieved otherwise.By choosing to make your material emissive you can turn it into a light source which glows and can be given any shape and texture. This gives you a scope to be even more creative.

The glow from emissive materials can be used for television or computer screen, exit sign or even for the brake lights of a car. They can also be used where artificial lights cannot be used such as to create the effect of recessed ceiling light.

Deciding when to use emissive materials as opposed to artificial lights can be a difficult choice. Using the right type of lightning can help in the project appear more real. This article will guide you through the process of using emissive lights.

Definition of Emissive Material

These are self-illuminating materials which means that these materials can emit light across their surface. The intensity of the glow can determine how the surround area lights up. Emissive materials can be used to create complex forms of glow which allows you to be creative.

In rendering realistic scenes Global Illumination is a key element and emissive materials belong to the global illumination calculation. With the GI calculation light bounce creates an indirect source of light which illuminates areas without artificial light or direct sunlight. Emissive materials which are part of the GI calculation therefore emit indirect light. The emission materials cannot be used to simulate artificial light. Here is a list of instructions on how to make materials emissive using SketchUp- Using the Enscape?s material editor it takes two clicks. First of all, open the Material Editor with a click on the button in the Enscape ribbon, or by selecting Enscape Materials in the Enscape dropdown menu. Next by using the SketchUp pickup tool select the material you want to make emissive. This gives you more control on the various settings related to the emissive materials.

The surface of the material emits a bright light which casts soft shadows. The light of the emissive material does not bounce around many corners as it has one bounce less than artificial light. By adjusting the Luminance slider, you can change the brightness of the material. As the Global Illumination is switched off in Enscape?s Draft Mode the light from the emissive materials will not bounce. The surface will be bright but the lighting will not illuminate the scene.

Often emissive materials can be noisy and cause the fireflies effect. If you come across this effect, increase the size or decrease the brightness of emissive surface. It is advisable to use emissive surfaces as large as possible to avoid noise.

The versality of emissive materials is in the fact that it can illuminate both colors and textures. By selecting a color from the drop-down menu in the Enscape Materials Editor you can apply a color to your emissive material.

Your material color can be matched with the color emitted as light from the emissive material by copying the color value out of the Advanced tab of the albedo color drop down menu in the same space in the emissive color menu.

The emissive materials do not come without drawbacks. If the geometry that was applied on the emissive material is not visible on screen the light emitted by the surface might not contribute to the actual light level in the scene. If you face such problems try to change the perspective of the camera until the geometry is visible again and the light returns as well.

By applying emissive materials in every object which glows will help you enhance your scene further. Try to use emissive materials with artificial lights. Enscape does not render actual light source therefore in the final outcome only the lighted area will be visible.

Emissive materials can be used to achieve the LED light effect where artificial light usage might be difficult. Such as in the case of recessed ceiling lighting, or LED lights that are installed along the tops of cabinets. Such lights are visible both in residential houses and office buildings as well as stores.

Using artificial lights for the LED light effect can be difficult whereas emissive material will help you achieve the desired result with ease by just applying it to the right spot. By using emissive materials with color and texture you will also find visible reflections unlike other undirect light. Though there is no guarantee that the reflection will be completely accurate. It is better to keep it simple for the right result.

Difference between Emissive vs Artificial

To understand when to use which kind of light we have made a list below:

Size and shape: Emissive materials can be used to any geometry or size whereas artificial lights have pre-defined shapes and sizes.

Light: If the light is diffused it can be very noisy especially if the surface is small and bright. Artificial lights are noiseless and will be ideal to use in such situations.

Shadows: If you want soft blurry shadows then use emissive materials. In case you want sharp, defined light and shadow then it is better to use spot light instead.

Bounce light: Emissive material has one bounce less than artificial lights. This does not allow the light to bounce in multiple directions. Artificial lights are brighter as they bounce one time more.

Customization: Color can be added to artificial lights to create a desired effect and atmosphere. Emissive materials do not just allow you to add color but also texture, therefore, taking the idea of customization to the next level.

Performance: Adding a number of artificial light sources to your project can cause lagging even if you have a good graphics card. You can use emissive materials to replace artificial light sources as it will help in getting a better performance.

Visibility: If the light source is not directly visible to the camera then the emissive materials might seem to be turned off. Whereas, the light cast by artificial lights is always visible.

Light level adjustments: The light level can be adjusted collectively by using the Light Brightness slider in the Advanced tab of the Enscape Settings menu for artificial lights. To dim or turn off emissive materials you have to adjust them individually.

Source: The light source of emissive materials is visible. In case of artificial lights, the source is not visible only the light emitted is visible.

CONCLUSION

Emissive materials are easy to apply and customize and can help in achieving that sense of realism that your project might require. By using emissive materials for LED lights or computer screen it adds more to the representation of reality. Presenting in front of clients is not just about showing the project but rather about creating a surrounding which they can see for themselves. It is important to find the right balance between emissive materials and artificial lights. You must know which light to use for your desired result. So, choose the right light to create a beautiful project and impress you clients!

How and when to use Emissive Materials in Sketchup
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