Advanced Render R9
ADVANCED RENDER Programming Team Christian Losch, Philip Losch, Richard Kurz, Tilo Kühn, Thomas Kunert, David O’Reilly, Cathleen Poppe. Plugin Programming Sven Behne, Wilfried Behne, Michael Breitzke, Kiril Dinev, Per-Anders Edwards, David Farmer, Jamie Halmick, Richard Hintzenstern, Jan Eric Hoffmann, Eduardo Olivares, Nina Ivanova, Markus Jakubietz, Eric Sommerlade, Hendrik Steffen, Jens Uhlig, Michael Welter, Thomas Zeier. Product Manager Marco Tillmann. QA Manager Björn Marl.
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Contents Introduction ..........................................................................................................1 Registration ........................................................................................................................................... 1 Installation............................................................................................................................................. 1 Training...............................................................
Highlights filter limitations .................................................................................................................. 47 5 Glow ................................................................................................................. 51 Render settings.................................................................................................................................... 51 Glow ...................................................................................
INTRODUCTION • 1 Introduction Welcome to Advanced Render, the ultimate CINEMA 4D module for rendering with realism. With Advanced Render you will be able to add realistic lighting to your scenes with ease; simulate the beautiful patterns of focused light known as caustics; apply accurate depth of field; use post effect filters for highlights and glow to create realistic effects such as the sun being reflected by high-gloss car paint, and much more.
1 Radiosity
RADIOSITY • 5 1 Radiosity Radiosity gives you an easy way to enhance the realism of your renders. Radiosity simulates the natural behavior of light, bouncing rays from surface to surface to produce photographic quality illumination. Render settings For a general introduction to radiosity, look up ‘what is radiosity?’ in the index. Image © Andreas Calmbach. You use two dialogs to set up radiosity.
6 • RADIOSITY The Object Animation mode takes slightly longer to render than the Standard mode but the improved quality is usually worth the wait. Object Animation works as follows: - The first animation frame is calculated as usual (shading points will be created). For the ARNOLD look, set the mode to Stochastic and render. Image © Bernd Seeger. The radiosity engine will then use an algorithm that generates a grainy look that is characteristic of the ARNOLD renderer.
RADIOSITY • 7 Prepass Size When you render a radiosity scene, a prepass image is rendered first that displays the shading points as dots. This setting defines the ratio of the prepass image size to the final render size. The default value is 1/1 — always use 1/1 for final rendering. Lowering the setting reduces render time but also lowers the render quality. Diffuse Depth A poor result with 3% Accuracy. This setting is the maximum number of reflections and refractions for each ray of light.
8 • RADIOSITY If your scene has lots of areas that are not lit directly by a light, such as underneath a table or around dark corners, then you may wish to increase the number of stochastic samples. As samples hit a surface, they will be radiated in all directions so if you need to bounce your light around 2 corners, very few samples will actually reach this area because they will have been dissipated before they reach this part of the scene.
RADIOSITY • 9 To summarize: Set Min Resolution to scene length ÷ biggest gap between shading points. Set Max Resolution to scene length ÷ smallest gap between shading points. If you notice artefacts in the rendered image such as dark patches, gradually increase the values for Accuracy and Max Resolution. The artefacts should disappear once the values are sufficiently high. Recompute Figure 4: A good Max Resolution setting.
10 • RADIOSITY Save Solution If you enable this option, the radiosity data is saved in the scene’s ‘Illum’ folder when you render — the folder will be created if it doesn’t exist yet. Depending on the Recompute setting, the saved data can be reused to speed up future renders. Material Editor / Attribute manager settings If you change the scene significantly, radiosity will need to be recalculated to ensure an accurate effect (set Recompute to Always).
RADIOSITY • 11 Saturation Similarly, within the material settings of glass objects you can disable Receive so that the glass is not illuminated by the radiosity. Doing both of these will reserve the samples for objects where their effects will be noticeable. Another important measure is to keep your geometry clean.
12 • RADIOSITY Examples Because radiosity calculations are complex, it is very difficult to give general advice on which parameters need to be adjusted and by how much in order to arrive at the optimum result. In these examples, each row demonstrates the effect of changing a particular radiosity parameter. Use these examples as a rough guide only; the best values to use will depend on the nature of your scene.
RADIOSITY • 13 The example scenes were lit using a colored light source and a Sky object without a material. For the first three rows of pictures, the bottom half of each picture shows the result of rendering in the Stochastic mode; the stochastic parameters are given in brackets. The values used are shown in red. The parameter that changes across the row is shown at the top of the list. What is radiosity? Radiosity is an option that improves the photorealism of rendering.
14 • RADIOSITY Avoid using a large sphere in place of the Sky object; otherwise, the radiosity effect will take longer to calculate and will also be less accurate. This is because the sphere will change the length of the geometry in the scene, causing the distance between shading points to change. For more details, see ‘Min Resolution, Max Resolution’. The lighting could be improved further still by using a HDRI in the sky’s material.
RADIOSITY • 15 At this point, the various surfaces hit by the stochastic samples are taken into account to calculate the indirect light for the shading points. (The shading points are those points hit by the camera rays — the points that created the first generation of stochastic samples.) Finally, the values for the shading points are interpolated to calculate the indirect light for each image pixel.
16 • RADIOSITY Types of HDRI There are three main types of HDRI: HDRI Latitude/ Longitude, HDRI Light Probes and HDRI Horizontal/ Vertical Cross. HDRI Latitude/Longitude Without HDRI. These images are distorted in such a way that they can be mapped onto a sphere (or a Sky object) using spherical mapping which produces perfect results. This type of HDRI works best in CINEMA 4D. Other types of HDRI can be converted to this projection type as described later in this chapter. HDRI Light Probes With HDRI.
RADIOSITY • 17 HDRI Horizontal/Vertical Cross These HDRIs are laid out like an unfolded cube and are designed to be mapped onto a cube that surrounds the scene. In CINEMA 4D, however, we recommend using the Latitude/Longitude type instead. Usage At www.debevec.org/Probes/ you’ll find a number of HDRIs that you can use for testing. HDRIs can be used as textures in the Color channel or Luminance channel of materials. When using a Sky object, you can use it in either of these channels.
18 • RADIOSITY Convert HDR Cross, Convert HDR Probe Some HDRIs come as Probe or Cross projection types. To get the best result in CINEMA 4D, these should be converted to Latitude/Longitude (spherical) maps and projected onto a Sky object. For this purpose there are two plugins included — Convert HDR Cross and Convert HDR Probe — which are available from the Plugins > Advanced Render menu. Choosing one of these commands opens a file selector. Select the HDR Probe or Cross image that you want to convert.
2 Caustics
CAUSTICS • 21 2 Caustics Render settings Image © Janine Pauke. With Advanced Render’s powerful caustics engine, you can create realistic patterns of focused light such as the bright patches that a whiskey tumbler casts onto a wooden floor. For a general introduction to caustics, including commonly-used terms, look up ‘What are caustics?’ in the index. You use three dialogs to set up caustics.
22 • CAUSTICS Volume Caustics Enable this option to switch on volume caustics. A lower Step Size produces a brighter effect. This is because more values are saved in the photon tree over the same distance. Sample Radius (volume caustics only) This specifies how close photons must be to one another in order to be interpolated. Higher values tend to produce better results but take longer to render. If you notice individual spots or dots in the render, increase the Sample Radius.
CAUSTICS • 23 Always Caustics data is always recalculated when you render. This is the default setting since it ensures a correct effect each time you render. Never Samples set to 1. Caustics are not recalculated when you render. Instead Advanced Render speeds up rendering by reusing the data in the scene’s ‘Illum’ folder. If this folder is not found, an alert appears. To remedy, set Recompute to First Time or Always.
24 • CAUSTICS Material Editor / Attribute manager settings Radius = 1; individual photons can be seen as points of light because they are not interpolated together. You can refine the caustics effect for each material using the caustics settings on the Illumination page of the Material Editor or Attribute manager. Generate Caustics, Strength Enable this option if you want the material to generate caustics. Enter the strength of the effect into the input box. Radius = 10.
CAUSTICS • 25 Samples This defines the maximum number of photons within the Radius that are used to calculate the effect. For example, if you enter a value of 100, up to 100 photons will be evaluated — any photons in excess of this number are ignored. Samples and Radius both affect the quality of the effect. Light settings To summarize: more samples per radius means a more accurate image. Increasing the Radius means more blur but a longer render time also.
26 • CAUSTICS The render time for caustics depends largely on the number of photons used, so aim to use only as many photons as the effect needs. The appearance of the caustics effect, i.e. its sharpness, is defined on the Illumination page of the Material Editor (see ‘Radius’ and ‘Samples’). Volume Caustics Surface caustics with high Energy (20,000). This defines the total starting energy for the surface caustics photons. The Energy value mainly controls the brightness of the caustics effect.
CAUSTICS • 27 This defines the total starting energy for all volume caustics photons. It affects the brightness of the effect as well as the maximum number of reflections or refractions for each photon. What are caustics? Caustics are patterns of focused light created by curved surfaces that are reflective or refractive. Photons This parameter controls the accuracy of the caustics effect. Increasing the value produces a better effect, but higher values mean longer render times also.
28 • CAUSTICS – A surface caustics effect shows up on object surfaces only — examples are the transparent sphere and the ring (in both cases, the effect shows up on a surface: the floor). – Volume caustics are visible as they pass through 3D space — they do not need a surface to illuminate. See Figure 3.
CAUSTICS • 29 The volume caustics algorithm Volume caustics are calculated in a similar way to surface caustics. First you need the following: - A volumetric light source to send out photons — enable volume caustics (Attribute manager, Caustics page of the light source); - An object with a material that generates volume caustics — the material must be transparent or reflective or both. The object must be curved in a way that focuses light.
3 Depth of Field
DEPTH OF FIELD • 33 3 Depth of Field With Advanced Render’s Depth of Field filter you have complete control over the sharpness of your pictures. For example, you can blur in front of the focus only, behind the focus only, or both. Using gradients, you can easily modify the progression from sharpness to full blur. In addition you can add a tint to your renders that gets stronger towards the horizon, for effects such as atmospheric perspective where the strength of a blue tint suggests depth.
34 • DEPTH OF FIELD To use Distance Blur, ensure that the scene has a camera (Objects > Scene > Camera). Ensure also that the camera has been linked to the viewport that you want to render (viewport: Cameras > Scene Cameras). In the Object manager, select the camera. In the Attribute manager, click the Depth tab to access the following settings. Figure 1: Rear blur only. Scene by Stephan Oberlaender. Of particular importance are: - Target Distance: the distance from the camera to the focal plane, i.e.
DEPTH OF FIELD • 35 Autofocus This option can be enabled to simulate the autofocus feature of a real camera. The object in the center of the view will become the focal point, i.e. the object in the center will be perfectly sharp. So that the object does not have to be exactly in the center, you can enter a tolerance value. The maximum value of 100% allows the object to be anywhere in the view. With lower values, the object must be closer to the view’s center to trigger the autofocus.
36 • DEPTH OF FIELD Smooth Knot To access all gradient parameters, click the small black triangle to the left of the gradient The gradient is similar to gradients in other applications that you have probably seen before. The handles on the bottom of the gradient, known as knots, are used to set the color and position of colors in the gradient. To add a knot just click in an empty area below the gradient and a knot of the color at that position will be added.
DEPTH OF FIELD • 37 Edit Alpha, Display Result The context menu for gradients Three commands are available for gradients via a context menu. To access the context menu, rightclick the gradient (Windows) or Command-click the gradient (Mac OS). Invert Knots Some gradients such as those for tint have two further options: Edit Alpha and Display Result. These options give you three gradients in one.
38 • DEPTH OF FIELD Lens Details Tint Using the settings on the Lens Details page, you can simulate the popular movie effect where objects that are brightly lit in places slip out of focus. Artefacts will appear in the bright areas. Use the Lens Details to adjust these artefacts. Using these parameters, you can add tints that take the scene’s depth into account.
DEPTH OF FIELD • 39 2. Use Ranges enabled, Use Camera Ranges enabled. Here the camera parameters are End, Start, etc. This works in the same way as described for Distance Blur. Use a camera to help define the tint ranges. 3. Use Ranges enabled, Use Camera Ranges disabled. Do not confuse these parameters with the like-named parameters of the Camera object. The tint range is defined by the values Front Start, Front End, Back Start and Back End (not the camera parameters) based on the camera’s focus.
4 Highlights
HIGHLIGHTS • 43 4 Highlights With Advanced Render, you have great flexibility when adding lens flares and glows to your pictures. Dozens of parameters enable you to adjust almost any aspect of the glow, from the number of beams to the size of each element. In addition, you can add flares and glows to specular highlights to achieve complex effects with ease, such as jewels that sparkle, flying logos where metallic or shiny objects catch the light or water surfaces that shimmer on a sunny day.
44 • HIGHLIGHTS Render settings Effects Note that nonclamped colors are no brighter on screen than pure white. However, restricting effects such as highlights to these colors enables you to achieve a sense of intense light in your pictures. Keep in mind that if you set the value too high, the threshold may not be reached and, as a result, no highlights will be added. Minimum Flare Intensity, Maximum Flare Intensity These parameters define the intensity of the highlights.
HIGHLIGHTS • 45 Glow Editor From top left to bottom right: Fine Regular, Fine Random, Wide-angle, Zoom, Camcorder, Searchlight, Streaks 1, Streaks 2, Star 1, Star 2, Flashlight, Sun, Broken Star, Fine Yellow Star, Soft Streaks 1, Soft Streaks 2, Blue. Use Object ID The Object ID corresponds to the object buffers defined in the Compositing tag. Suppose there are two objects in the scene and you want each object to use its own highlights settings.
46 • HIGHLIGHTS Size Beam properties Here you set the overall size of the glow element as a percentage of the screen’s size. A value of 100% represents the distance from the center of the screen to the edge of the screen. Beams R (aspect ratio) This value defines the aspect ratio for the glow. A value of 1 results in a circular glow, whereas values greater or less than 1 produce a horizontal or vertical ellipse. Beams consist of separately editable elements.
HIGHLIGHTS • 47 Breaks Add breaks to the beams by entering the number of breaks here. The breaks are added to the gaps that already exist between beams. Use the Width parameter (described below) to control the size of the breaks. Width Defines the size of breaks. See ‘Breaks’. Random Distribution For a random arrangement of beams, enable this option. Random Beam Length Enable this option if you want the lengths of the beams to be varied.
5 Glow
GLOW • 51 5 Glow Advanced Render gives you a powerful filter for creating glow effects. With it you can simulate the glow of incandescent lights, lightning bolts, LEDs, neon lights, monitor screens, the reflection of the sun by high-gloss car paint and much more. The Glow filter also enables you to: - Control glow transparency. Do not confuse the Glow filter with the Glow channel for materials.
52 • GLOW Object ID Intensity The Object ID corresponds to the object buffers defined in the Compositing tag. Suppose there are dozens of objects in the scene and you want only one of them to glow. In the render settings, on the Effects page, add the Glow post effect and set Object ID to 1. Assign a Compositing tag to the object that should glow and, in the tag, enable Buffer 1. The glow is now restricted to this object. The Intensity is a measurement for the transparency of the glow.
GLOW • 53 Back Intensity This parameter controls the glow effect for dark surfaces. Using Back Intensity you can fine-tune the transition from glowing areas to non-glowing areas. To reduce the amount of glow for dark areas, set Back Intensity to a high value. Use a low Back Intensity value for negative glow. Luminosity High Back Intensity value. The glow effect is usually additive and brightens pixels. Using Luminosity you can reduce the glow’s additive nature, causing the glow to darken.
54 • GLOW Color If the Use option for Color is disabled, the glow will be the same color as the material. To define a different color for the glow, enable the Use option, click the color box and choose the desired color (to access color sliders, click the triangle that’s next to the color box). Luminosity set to a high value. Back Luminosity This parameter gives you a more refined way to control luminosity by checking the brightness of the rendered pixels.
GLOW • 55 Glow Edges You can restrict the glow effect to object edges by enabling this option. To make the object’s edges glow with a uniform color — regardless of the rendered brightness — choose a glow color and set Balance to 100%. Zoom Scale disabled. The glow still has the same thickness when you zoom the object. For uniform edge glow, enable Glow Edges and set Balance to 100%. Zoom Scale There are two ways to zoom objects in the viewport: 1. By increasing the camera’s Focal Length value. 2.
56 • GLOW Balance The Balance parameter controls how bright the rendered pixels must be in order to trigger glow in those areas. With the default value of 0%, only the brightest areas will glow. With a value of 100%, all areas will glow with the same intensity. However, note that a dark glow will be used for the dark areas. Use the Object ID parameter to restrict the glow to the desired objects.
GLOW • 57 Use Key Color Distance Attenuation Glow restricted to a key color. You can restrict the glow to a particular color. Use the color box to choose this ‘key color’. Since most rendered surfaces are gradations of color rather than a single tone, you can also specify a tolerance value for the key color, which you enter into the Color Variation box. If you set Color Variation to a value that is too low, such as 0%, you may find that only a few pixels will glow.
58 • GLOW Distance Position Surface Normal Attenuation There are two settings. Z-Buffer Start Range and End Range refer to the Z-buffer, i.e. the distance from the camera to the object’s surface. 3D Pos Start Range and End Range refer to the position of the object’s axis in 3D space. The glow spreads out radially from the axis. Using gradients You can use gradients to refine the following glow properties from the Glow page: Size, Intensity, Luminosity and Color (see ‘Glow’ entry).
GLOW • 59 Using gradients Noise You can use gradients to refine the following glow properties from the Glow page: Size, Intensity, Luminosity and Color (see ‘Glow’ entry). Exhaust fumes, flickering flames, lightning bolts and puffy clouds are just a few of the effects you can achieve with the help of noise. A small amount of noise can also add to the realism of most soft glow effects.
60 • GLOW Noise Type You have a choice of three noise types: Gaseous, Fire and Electric. Gaseous is ideal for puffy clouds, smoke and other cloud-like effects. Fire is for anything to do with fire while Electric produces streaks like the charges of a lightning bolt or plasma ball. High Intensity value. Low Intensity value. The intensity of a noisy glow also depends on the basic glow properties on the Glow page such as Intensity and Luminosity (see ‘Glow’).
GLOW • 61 Luminosity Scale Luminosity affects the settings for Color and Ground Glow. It controls the strength of additive mixing for these parameters when they are mixed with the other image elements. The fractal turbulences are scaled using this parameter. Luminosity set to a low value (bottom left) and a high value (top right). Color Here you can choose the color of the noise. Enable the Use option for Color, click the color box and choose the desired color.
62 • GLOW Details Ground Glow The Details parameter controls the amount of fractal branching. The minimum value of 1 generates the least amount of branching and is the quickest to calculate. Values greater than 10 should generally be avoided since they tend to produce very thin, almost invisible branches and take a comparatively long time to calculate. Noise usually affects the Ground Glow, causing the noise to glow. If Ground Glow is enabled, the noise is placed over the (unchanged) Ground Glow.
GLOW • 63 Glow filter limitations - Problems may occur in areas where glows are seen in reflections or behind transparencies. - If glow is calculated before depth of field, the depth of field will overwrite the glow. If glow is calculated after depth of field, inaccuracies may arise. - Glow cannot be used with the PyroCluster module.
6 Vector Motion Blur
VECTOR MOTION BLUR • 67 6 Vector Motion Blur To render VMB as a separate pass, on the Render Settings > Effects tab, click the Channels button and choose Post Effects from the menu that appears. The major advantage over scene motion blur is the fact that no intermediate frames need to be rendered, greatly reducing render times. Unlike object motion blur, it’s much more precise and functions even on circular or curved paths. Furthermore, you can use it with bones and any other types of deformer objects.
68 • VECTOR MOTION BLUR Render settings Shutter Angle Density set to a low value (left) and high value (right). The Density value defines the coverage of the blur in the image. The Phase value defines the position of the blur. The following Phase values should serve as a reference: 0%: behind the object. 50%: the same length on both sides of the object. Shutter Angle set to a low value (left) and high value (right). The Shutter Angle defines the length of the blur trail.
VECTOR MOTION BLUR • 69 Sample Radius set to a low value (left) and high value (right). Samples allow you to set the resolution or smoothness of the blur. Low values result in a grainy look, while more samples increase both the quality and the render time. The higher the Sample Radius, the less crisp the blur will look. Weighted Trails Weighted Trails disabled (top) and enabled (bottom).
7 Subsurface Scattering
SUBSURFACE SCATTERING • 73 7 Subsurface Scattering Using subsurface scattering Follow these simple steps to use SSS on an object: - Create a new material and load the SSS shader into the material’s luminance channel. Adjust the Scattering Length — make sure it’s shorter than the object. - For now, ignore all SSS parameters except Strength. Modify this setting until it produces the desired effect. - Adjust the Absorption Filter color and the Absorption parameter.
74 • SUBSURFACE SCATTERING Material Editor / Attribute manager settings The gradient gives you an excellent way to simulate bleached materials such as a red plastic toy bleached white at the edges by prolonged exposure to the sun. Strength Strength set to a low value (left) and high value (right). Absorption Filter These colors will only appear in the rendered image if they are also present in the penetrating light. If in doubt use a white light, which contains all colors.
SUBSURFACE SCATTERING • 75 Absorption Minimum Thickness This setting defines the thinnest surface that a ray of light will pass through without diminishing. Problems that stem from too hard and unrealistic edges are thus avoided. Usually, you don’t have to adjust this parameter much. Scattering Length Absorption Filter set to a low value (left) and high value (right). Absorption is measured in meters and represents how far the light can pass through the material before it is fully absorbed.
8 Sub-polygon Displacement
SUB-POLYGON DISPLACEMENT • 79 8 Sub-polygon Displacement If you have previously used bump maps, you can now use the maps with SPD on the displacement page instead of in the bump channel for better results in most cases. Since SPD is calculated during the rendering process — as is the case with normal displacements — it is not possible to create geometry via Current State to Object.
80 • SUB-POLYGON DISPLACEMENT Material Editor / Attribute manager settings Subdivision Level Balls of slime (two sphere primitives with their Render Perfect option disabled) with a subdivision of 2,4 and 8 (from bottom to top). You’ll find the SPD settings on the Displacement tab in the Material Editor or Attribute manager. There is also an option in the preferences — Sub-Polygon Displacement Memory MB — that controls the amount of memory assigned to SPD.
SUB-POLYGON DISPLACEMENT • 81 Example A Subdivision Level of 8 would result in the following (internal) polygon count: Cube: 8*256*256 = 52,488 polygons. Plane: 400*500*500 = 26,214,400 polygons. Round Geometry Round Geometry disabled (left) and enabled (right). To apply the earth texture to this platonic body (icosahedron) without smoothing, simply disable the option. Round Geometry and HyperNURBS Round Geometry disabled (left) and enabled (right).
82 • SUB-POLYGON DISPLACEMENT Map Rounded Geometry Keep Original Edges This option determines whether the rounded geometry should be used to define the texture coordinates. In most cases this will lead to more intuitive results. It can also lead to fewer artefacts. Because the calculation can take up to 10% longer and in some cases the projection must be onto the non-rounded geometry, you have the option to disable this feature.
SUB-POLYGON DISPLACEMENT • 83 The benefit to enabling this option is that in most cases it will ensure a soft, continuous transition of the SPD over Phong edges. If Best Distribution is disabled (only advisable when Type is set to one of the intensity modes), the individual displacements will point up, which can lead to “inflated” displacements as can be seen on the top right edge of the second cube in the example.
9 Tutorial
TUTORIAL • 87 Radiosity For this tutorial we’ll use Advanced Render’s powerful radiosity engine to render an office lobby scene with natural lighting. There are two things to remember when modeling a scene for radiosity: 1. Controlling light is incredibly important. Radiosity scenes usually look best with hard shadows. Unfortunately, when rendering hard shadows, we will bump into floating point errors that can cause light to seep into cracks (the place where polygon planes come together).
88 • TUTORIAL Create a new material and name it Sky. In the Material manager, double click on the new material’s preview to open the Material Editor. Disable the Color channel for this material. Enable the Luminance channel and open its settings page. Add a touch of cyan to the skydome’s material to simulate the sky’s color. For this channel we want a white, slightly leaning towards cyan, for a bright sky simulation. (R=90%, G=100%, B=100%, Br=100%.) Disable the Specular channel.
TUTORIAL • 89 Adding Lighting All we need to do is add a single light to the scene, simulating the Sun, and let the radiosity calculation do the rest of the work. Create a target light (Objects > Scene > Target Light) and name it Sun. In the Object manager, click on Sun to display its settings in the Attributes manager. On the General page, change the light’s Type to Parallel and make the color of the light slightly yellow to imitate the sun. (R=100%, G=100%, B=96%, Br=170%. Or RGB = 255, 155, 244.
90 • TUTORIAL The target object for the light will automatically be placed at X=0m, Y=0m, Z=0m. We can leave it there. That’s all you have to do for the lighting part of this scene. In the next section, we’ll be setting up the rendering.
TUTORIAL • 91 Rendering the Scene Open the Render Settings (Render > Render Settings). We will be using the raytracer for this scene. This will give a high quality final render. Set Antialiasing to Best and set Filter to Still Image. As a rule, we should leave all the rest of the settings on the first page at their highest level. This is because there is no increase in rendering time unless they occur in the scene. (This scene will use Transparency With Refraction and Reflections for All Objects.
92 • TUTORIAL Set Stochastic Samples to 200 and Resolution to Min 100, Max 200. These setting will give us higher precision in the corners. Go to the Save page. Set the Format to TIFF. Click the Path button, select a location and name for the rendered image and click Save. Go to the Multi-Pass page. Enable the Enable Multi-Pass Rendering option. This will save a new image with a separate layer for each channel we set on the Multi-Pass page.
TUTORIAL • 93 Close the Render Settings dialog. Click the Render To Picture Viewer button. The file will begin rendering. First there will be a pause while various calculations are made, then a pre-pass phase when the scene is assessed for complexity, and then the final render pass will be performed. The radiosity settings we have used should give a good result in a reasonable time.
Index
INDEX • 97 Symbols 3D Pos 58 A Absorption 75 Absorption Filter 74 Autofocus 35 B Background Blur 35 Back Intensity 53 Balance 56 Blur Strength 33 C Camera 34 Camera animation 5, 6 Caustics 21 Falloff 27 Receive 24 Settings 24 Surface 27 Troubleshooting 29 Volume 27 What are caustics? 27 Cloud 60 Convert HDR Cross 18 Convert HDR Probe 18 D Depth of Field 21, 33, 43 Autofocus 35 Background Blur 35 Blur Strength 33 Camera 34 Distance Blur 33 Limitations 39 Using gradients 35 Distance Attenuation 57 Distan
98 • INDEX Lens Shape 38 Lens Sharpness 38 Limitations Depth of field 39 Glow 63 Highlights 47 M Material Editor 24 Maximum Flare Intensity 44 Min/Max (Nonclamped Color) 56 Multiple use iii N Network operation iii Noise 59 Angle / Drift 62 Brightness 60 Color 61 Density 60 Details 62 Ground Glow 62 Intensity 60 Luminosity 61 Noise Type 60 Peak Blend 61 Phase 62 Scale 61 Static Pos 62 Stretch 62 Nonclamped Color Attenuation 56 O Object ID (Glow) 52 Object ID (Highlights) 45 P Peak Blend 61 Phase 62 Phot
