'Creating A Pontiac Trans Am' Part 5
'Creating A Pontiac Trans Am' |
by Amirhossein Erfani |
| Ok now we need to put the main render on this layer, but we only need the car not the environment. So let’s use the third image to mask the image over the background layer. To do the mask effect, first drag and drop the main image on the background layer and then click on the Add Layer Mask parameter under the Layers panel. Then Alt + Click the second layer slot and just copy and paste the mask image to get the result needed. Then select the layer and choose Darken in the Blending Mode list. As I said you may get different results depending on different color types, shadow types and other factors so you may want to try other modes, but the process is the same. After applying the changes on the second layer we should have the result shown in Fig.19. |
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Fig.19 |
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So far we have brought the missing smooth shadows back, but it’s not yet the result we are looking for. So duplicate the layer with different Blending Modes and different Opacity values to get a better result. The new layers have various blending modes like Color Dodge, Lighter Color, Soft Light and Hard Light to get a clearer image. Take a look at this image to get the idea and take note of the blending modes and their opacity values (Fig.20). |
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Fig.20 |
So that was the studio render of our Pontiac. Remember that we chose this method to get a good render with the least time, but if you want to get the same result directly from mental ray with no post processing you can let the engine process and create the GI. To do so, using a Skylight would be good idea. Create a Skylight and activate Global Illumination and Final Gather in the mental ray settings. Test your renders with the lowest sampling quality and try out different lighting setups to get the result desired. Also using a HDRI map in the environment background will help your image to get more realistic reflections and quality. And here’s the finished image (Fig.21). |
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Fig.21 |
'Creating A Pontiac Trans Am' Part 4
'Creating A Pontiac Trans Am' |
by Amirhossein Erfani |
| Set the Intensity of the lights to a low value (because of their quantity) and set the Hotspot Parameter to the minimum value with the Falloff Parameter at a higher amount. Leave the shadow type to the default type (Ray traced) and click Render. You should get a result like this (Fig.14). |
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Fig.14 |
As we are not using GI and Final Gather for this render, to get a better result we’ll blend a few passes in Photoshop. Take Fig.14 as one of the passes, but for the smooth GI simulation and perfect shadow settings we will use another method. Press F10 to reach the Render Panel. Click on the Processing tab and check the Enable option under Material Override section. Click the material and select mental ray material from the list. Open the material editor and drag the override material to an empty slot. Select the Surface map and assign an Ambient/Reflective Occlusion to its map channel. These settings will help you get a clear pass for the missing GI. There’s a Samples parameter which could be set to 16 or 32 for test renders, 512 or 1024 for final renders. Check out the settings in Fig.15. |
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Fig.15 |
Let’s render with the parameters set as above. We will get a result like this (Fig.16). |
Fig.16
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'Creating A Pontiac Trans Am' Part 3
'Creating A Pontiac Trans Am' |
by Amirhossein Erfani |
| Now it’s time to discuss the Pontiac Eagle logo on the hood. There are a few simple steps. Start with an empty material slot and set it to Composite. As you may know, there’s a Base Material in the composite box, which we should set to the Car Paint we just made. The next step is to take the Mat1 and set it to a Standard material. This material which comes completely over the Base Material would be the Eagle Sign. So let’s keep it simple; use a Blinn shader with any color you desire. Now if you render you’ll see the hood completely covered with the upper layer, the Standard material. The only thing we should do now is to mask this material over the Car Paint with a texture like this (Fig.09). |
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Fig.09 |
Click on the Opacity Map Channel and set it to Bitmap. Select the black and white eagle texture and then click on the Show Map In Viewport option to set the coordinates. The final step is to apply a UVW Map modifier to the hood object, with simple planar mapping. We can also use the same method for the tires. Here you can check out the material settings and the result achieved (Fig.10 – 12). |
Fig.10 |
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Fig.11 |
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Fig.12 |
After setting the materials, it’s time to set the scene for rendering our model. We start with creating the light sources. Add a few MR Spots around the objects; I created one and copied a few more as instances, from different angles. For the white boxes, just create some boxes (or any other standard primitive) with this material. Assign a standard material to the objects, with the Self Illumination parameter set to 100, and a Falloff map for the diffuse channel. Then set both colors of Falloff to pure white, scroll sown to the Output tab and set the RGB Level Parameter a number greater than 1.5. And we’re done here (Fig.13)! |
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Fig.13 Page 3 |
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