This tutorial will focus on how to achieve realistic ceiling light in night scene, rendered using VRay 3.4 for SketchUp. Here we will explore different lighting options available in VRay 3.4 to create artificial light with proper illumination in night scene setting. The following VRay lighting options that are suitable for depicting ceiling lights includes (1) VRay plane light and (2) emissive light. Here, I will show you the different methods on how to achieve ceiling light effects using different VRay lights. Before we move on to the tutorial proper let me guide you to the SketchUp model and VRay settings exclusive for this tutorial.
INITIAL SETUP
Here are the SketchUp model scenes with assigned materials as well as VRay settings for rendering procedure. Later, we will be adding 3-D model entourage to the scene during the test render in order to see the effect of VRay lights in different object materials.
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| In ‘VRay asset editor’, set the framing in square with 1500x1500 pixels. Going back to SketchUp work space, make a model with four faces. Make sure the ceiling is position in front face (white face) facing downward. When done, save the scene. |
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| For the material settings, go to ‘SketchUp material dialogue box’ and choose any available materials appropriate for your model. Go to ‘VRay Asset editor’> ‘Materials’ and add reflection to the tiles floor material. |
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| For the environment, go to ‘VRay Asset editor’> ‘Lights’>‘Sunlight’ and uncheck the ‘Enabled’. When done, go to ‘Settings’ and click the ‘Background’ and ‘GI Skylight’ one at a time, then select the ‘Color’ option. Adjust the color level from black to gray. |
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| For the entourage, which will be later use for test render, I assigned different materials such as wood diffuse texture, gold plate metal, chrome polished, porcelain green color, and plastic. |
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| For post-production, add the following render elements to your render settings: Denoiser, Raw Light, Raw Shadow, and Raw Reflection. |
Method #1: Using the VRay plane light as a model for ceiling light
VRay plane light is the most common feature in VRay for SketchUp that can be used as a model or component to replicate a ceiling light. This method is somehow a painstaking task since you have to manually arrange the VRay plane light accordingly on the ceiling to make the ceiling light more realistic. Here, I will show you the step by step procedures for this method.
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| STEP 1-3: Go to to ‘VRay Asset editor’> ‘Material’ then select ‘wood planks’ material and apply it on the ceiling. STEP 4: Click the ‘VRay Plane light’. STEP 5: Going back to SketchUp work space, adjust the size and shape of the VRay Plane light similar to the size of an actual square ceiling light. STEP 6: Place the VRay plane light on the ceiling surface. Select the VRay plane light model then use the command Ctrl+’Move ‘ in order to make a copy of an object while moving into places. STEP 7-8: Go to ‘VRay Asset editor’> ‘Lights’> “V-Ray Rectangle light’. STEP 9: Under ‘LightRectangle>’Main’ change the intensity value of the light from 30 to 400. STEP 10: Add the 3-D entourage to the scene. STEP 11: When done click the render button. |
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| Here is the render result for method #1 with render elements |
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| Method #1 render result raw image |
Method #2: Using the VRay plane light as texture for ceiling light
The most practical way of rendering a ceiling light is by using the VRay plane light as a texture instead of using it as a model or component. During the modeling process, this method will somehow produce less polygon counts which include faces and edges. This particular method is applicable for large scale model such as office interior render or rendering a building scene.
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| STEP 1: Prepare the texture. Here are the images that we can modify to create a ceiling light texture. |
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| STEP 2: Using the ‘Photoshop’, combine both images and adjust the scale. |
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| STEP 3: Create a duplicate layer for the ceiling and reduce the brightness of the image. Go to ‘Image’> ‘Adjustment’> ‘Exposure’ and adjust the value to make it darker. When done, let’s name it ‘Ceiling dark’ |
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| STEP 4: Make a duplicate copy of ‘Ceiling dark’ layer and change the blend mode from ‘Normal’ to ‘Hard Light’ for both layers. |
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| STEP 5: Using the ‘Eraser tool’, gently erase the middle part of the ‘Ceiling dark’ layer |
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| STEP 6: Go to ‘Ceiling dark copy’ layer. Adjust the size of the ‘Eraser tool’ and gently erase the whole layer image. |
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| STEP 7: When done, save the image file in JPEG format. Here is the final texture. |
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| STEP 8: Going back to SketchUp, cover the entire ceiling with ‘VRay plane light’. Make sure the front face is facing on the floor. |
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| STEP 9: Go to ‘VRay Asset editor’> ‘Lights’> ‘V-Ray Rectangle Light’, then change the value of ‘Intensity’ from 30 to 60. Under ‘LightRectangle’> ‘Main’, enable the ‘texture’ and click the ‘Load image’. |
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| STEP 10: To load the texture, click the ‘Bitmap’ and select the appropriate texture for the ceiling light. Expand the ‘UVW’, under ‘Repeat’, change the value of ‘U’ and ‘V’ from 1 to 2. When done, add entourage and click the render button. |
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| Here is the render result for method #2 with render elements |
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| Method #2 render result raw image |
Method #3: Using the VRay emissive light as texture for ceiling light
As an alternative to VRay plane light, I would recommend to use the VRay emissive light for reflective ceiling light. This method has almost the same procedures used in Method #2 from which a ceiling light texture is required. The advantage of using VRay emissive light is that you can add reflection effect on the ceiling. The only downside of using emissive light during the rendering is that there is no shadow emitting from the lights.
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| STEP 1: Select the ceiling surface of the model and then apply any available material in ‘SketchUp Materials’. Here, I choose ‘0001_PaleVioletRed’ from ‘Materials’> ‘Color-Named’. Select the ‘0001_PaleVioletRed’ from ‘V-Ray Asset Editor’> ‘’Materials’ and expand the selection. |
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| STEP 2: Under ‘VRayBRDF’, click the add image file in ‘Diffuse’. Expand the selection and select ‘Bitmap’ then add image file. Select the appropriate texture for ceiling light; use the same texture we used in Method #2. |
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| STEP 3: Select the texture from the model. To adjust the size of the texture, go to SketchUp Material Dialogue box’> ‘Edit’> change the value from .50 to 5 meters. |
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| STEP 4: Going back to ‘V-Ray Asset Editor’> ‘’Materials’, select the ‘0001_PaleVioletRed’. Click the ‘Add layer’ and select ‘Emissive’. |
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| STEP 5: Change the ‘Intensity’ value of emissive based on your preference. Under ‘Emissive’> ‘Emissive color’, load the texture image file. Use the same ceiling light texture from the previous method. |
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| STEP 6: Still on the ‘Emissive’ layer, go to ‘Transparency Color’ and load the ceiling light texture under ‘Bitmap’ option. Under ‘Manipulation’, check the ‘Invert Texture’. |
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| STEP 7: To add reflection, go to ‘V-Ray Asset Editor’> ‘’Materials’, select the ‘0001_PaleVioletRed’> ‘Reflection’> ‘Reflect’ then increase the level from black to white. Make sure that the ‘Reflection’ is checked. When done, click the render button. |
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| Here is the render result for method #3 with render elements |
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| Method #3 render result raw image |
As a summary, there are three ways on how we can render ceiling light in VRay 3.4 for SketchUp. Here, we were able to test different methods of rendering ceiling lights in VRay with various results such as render element outputs, polygon counts and render time. In terms or render elements, method #1 using VRay plane light as a model gives as complete outputs, while in method #2, using VRay plane light with texture produces no reflection at all. This is primarily due to the fact that VRay plane light is under the category of Lights and not considered as VRay material where in you can add a reflection layer. In method #3, using emissive light, there is a reflection but there are no results for raw shadow and raw light. Here, the emissive light is considered as VRay material and not a Light category. Thus, you can add reflection map on the emissive light layer but it cannot produce shadows emanating from its light. By looking at the result in polygon counts, the method #1 produces more edges and faces than method #2 and #3. In terms of render time, method #1 and #2 has less render time as compare to method #3 which is 4 times longer.
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| Summary Result |
As a conclusion, you can achieve realistic ceiling light render by using different VRay lights with different methods and techniques depending on your work demands. For instance, method #1 is more appropriate for detailing and small space model while methods #2 and #3 are suitable for massing, macro view, and building large models.
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| My other renders using VRay Plane Lights and Emissive Light |
Thank you and good luck!
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