Standard light sources in 3d max. Standard light sources

Understanding lighting in 3D graphics
In any three-dimensional graphics editor (Lightwave 3D, Maya, Softimage, 3ds Max, etc.), the realism of the rendered image depends on three main factors: the quality of the created three-dimensional model, well-made textures and scene lighting. The same scene, rendered under different lighting, can look completely different. When the position of light sources in the scene changes, the coloring of objects and the shape of cast shadows are distorted, and areas appear that are too flooded with light or too dark.
Creating realistic lighting in a scene is one of the biggest challenges in 3D graphics development. In reality, an incident ray of light undergoes a huge number of reflections and refractions, so it is very rare to find sharp, unblurred shadows. Another thing is computer graphics. Here, the number of incidences and reflections of the beam is determined only by the hardware capabilities of the computer. Until a certain point, 3D graphics were dominated by harsh shadows. The scene the designer works with is only a simplified physical model, so the rendered image does not always resemble the real thing. But despite this, the lighting in a 3D scene can still be brought closer to real life. To do this, you need to follow two rules:
* install light sources and select their brightness (parameters) so that the scene is evenly illuminated;
* set lighting visualization settings.

NOTE
Despite the fact that light sources are most often used to illuminate objects in a scene, sometimes light is used as an independent object, for example, to simulate a distant light in the night, a lighthouse, a star in the sky, etc.

The problem of lighting in images arose long before the advent of 3D graphics. Artists and photographers were the first to solve the problem of proper lighting, later - cinematographers, and now it has become vital for developers of three-dimensional graphics.
The most common method is lighting from three points (three-point system). This approach is successful when lighting a single object (for example, portraits in a photo studio); it may not be suitable for complex three-dimensional scenes. The choice of lighting depends on the number of objects, the reflective properties of their materials, and the geometry of the scene.
For lighting, it is also important what type of light source is used. For example, a directional light source allows you to concentrate attention on a specific object, while an omnidirectional point source allows you to illuminate the entire scene.

Stage lighting
So, for 3D models to look natural in a rendered image, they need to be properly lit. By default, 3ds Max 8 uses its own system, which evenly illuminates objects in a 3D scene. With this lighting system, there are no shadows in the final image, which looks unnatural. To make objects cast shadows, you need to add light sources to the scene. As soon as light sources appear in the scene, the lighting system used by 3ds Max 8 automatically turns off.
Light sources in 3ds Max 8 are divided into directional (Spot) and omnidirectional (Omni). The first category includes Target Spot, Free Spot, and mr Area Spot (used by mental ray). BCCHI etched lights include Omni and mr Area Omni (used by the mental ray renderer).
Directional lights are used primarily to illuminate a specific object or area of the scene. Using directional light sources, you can simulate, for example, the light of car headlights, the beam of a spotlight or flashlight, etc. Omnidirectional light sources emit light evenly in all directions. Using them, you can simulate, for example, lighting from electric lamps, lanterns, flame light, etc.
Regardless of which light source is used in the scene, it is characterized by such parameters as Multiplier (Brightness), Decay (Attenuation) and Shadow Map (Type of cast shadow) (Figure 13.1). By default, the Multiplier of any light source is 1, and the Decay option is turned off.
Since in real life light from sources obeys the laws of physics, the intensity of light propagation depends on the distance to the light source. If you need to simulate a realistic light source, then in the light source settings you need to set the Decay function, which is determined by the inverse dependence of light on distance or the square of the distance. The second option most accurately describes the propagation of light.
When creating scene illumination in relation to light sources, the following effects are often used.
* Volume Light - the light created by the source colors the space in the color of the source. In real life, this effect can be observed in dark, dusty or smoky rooms. A beam of light breaking through the darkness is clearly visible.
* Lens Effects - resembles the effect that is obtained in real life on an image when using special lenses with different lens systems. These can be highlights of various shapes, reflections, etc.
To use an effect, in the light source's Atmospheres & Effects settings rollout, click the Add button and select the desired effect in the Add Atmosphere or Effect window.

ADVICE
You can also add an effect to the scene by running Rendering --> Environment or pressing the 8 key. In the Environment and Effects window, go to the Environment tab (to add the Volume Light effect (Volume Light) or to the Effects tab (to add Lens Effects), then click the Add button to add one of the effects to the scene.

To configure the effect, use the Setup button in the light source's Atmospheres & Effects settings rollout. This will take you to the Environment and Effects window. In order for the program to calculate the effect, you must specify in its settings which light source the selected effect is applied to. Click the Pick Light button and then click on the light source in the projection window.

Rules for placing light sources in the scene
There are many techniques you can use to light a scene to hide minor imperfections and highlight important details. For example, to give volume to a three-dimensional model, it is enough to light it from behind. This will create a clear border, visually separating the object from the background. Another example: if you want to illuminate half of an object, then the other half should also be illuminated by a light source with low intensity. Otherwise, the shaded area of the 3D model will be unnaturally hidden in absolute darkness. This will be especially noticeable if the object is located with its dark side facing the wall. In this case, the light should be reflected from the wall and weakly emphasize the contour of the shadowed side of the object (this happens in reality).
Along with such techniques, there are also general recommendations on how not to light a stage. For example, the light source should not be located much lower than the illuminated object, as this will give the model an unnatural appearance. In reality, most often we see objects illuminated by a chandelier or the sun, so in 3D scenes the light source should be located from above. This gives the scenes realism.
Light sources with high intensity should be used very carefully. Lighting created with their help can cause strong highlights and distort the texture of the object. By default, the Multiplier parameter of all lights in 3ds Max 8 is set to 1. Try to avoid values exceeding this number if possible, and use the Decay parameter.

Realistic light sources, artificial and natural, emit light whose intensity decreases as you move away from these sources. All standard light sources in 3ds Max 8 can use varying degrees of attenuation - Inverse or Inverse Square. It can be selected from the Type list of the light source Intensity/Color/Attenuation settings rollout. The degree of attenuation that best corresponds to reality is Inverse Square, but it is not always convenient to use due to the fact that too strongly illuminated areas may appear near the source, and completely dark ones at a distance from it. A solution to this problem is to increase the Multiplier value while increasing the distance between the light source and the subject.
To illuminate the stage, it is convenient to use one main light source and several auxiliary ones. As the main source, you can use, for example, one of the 8 directional light sources available in the 3ds Max arsenal. The intensity of auxiliary light sources should be significantly less than the main one. In addition, auxiliary sources should not create shadows from objects in the scene. A lot of shadows can make a scene look cluttered.

ADVICE
When working on lighting, do not forget that in the properties of any light source you can specify which objects it will illuminate and which it will not. To do this, click the Exclude button in the General Parameters settings rollout and make the necessary settings in the window that opens. This feature is needed in order to rationally use program resources and not overload the already complex visualization process. Excluding objects from the area of influence of light sources can be considered a kind of scene optimization.

Thus, choosing the position of light sources in a scene is a rather difficult task. Poor placement of light sources can create too dark areas in the scene, and the objects themselves can be difficult to see due to insufficient lighting or, conversely, too bright light. Because each 3D scene has its own unique geometric characteristics, the location of the sources will be different for different scenes. For this reason, it is difficult to develop specific rules that can be followed to optimally illuminate a scene. Regardless, there are a few general tips to follow to avoid ruining your 3D composition with poorly placed lighting.
* You should not set the brightness value of light sources to greater than or equal to 1 unless absolutely necessary, as this may result in overexposed areas and unwanted glare.
* Keep in mind that objects illuminated from behind will appear slightly more three-dimensional in the final image.
* If there are several light sources in the scene, the brightness at a single point is equal to the total brightness of all sources in the scene.
* Having a lot of light sources in a scene can cause a lot of chaotic shadows, which will be unnecessary in the rendered image.
* If you want to achieve photographic realism, then to visualize the scene it is better to use special plug-in photorealistic visualizers, which in terms of rendering accuracy are an order of magnitude higher than the standard visualization module (Default Scanline Renclerer).

Characteristics of Light and Shadow Rendering Techniques
Light has three main characteristics: brightness (Multiplier), color (Color) and shadows cast from the objects it illuminates (Shadows).
When arranging light sources in a scene, be sure to pay attention to their color. Daylight sources have a blue tint, but to create an artificial light source you need to give it a yellowish color. It should also be taken into account that the color of the source simulating street light depends on the time of day. If the scene involves evening time, the lighting may be in the reddish shades of a summer sunset.
Various renderers offer their own shadow generation algorithms. The shadow cast from an object can say a lot - how high it is above the ground, what is the structure of the surface on which the shadow falls, what kind of source is the object illuminated, etc. In addition, a shadow can emphasize the contrast between the foreground and background, as well as “ display" an object that was not in the field of view of the virtual camera lens. Depending on the shape of the shadow cast by the object, the scene may or may not look realistic.
As we said above, a real beam of light undergoes a large number of reflections and refractions, so real shadows always have blurry edges. In 3D graphics, a special term used to describe such shadows is soft shadows. Achieving soft shadows is quite difficult. Many renderers solve the problem of soft shadows by adding a non-point light source, rectangular or other shaped, to the 3ds Max 8 interface. Such a source emits light not from one point, but from every point on the surface. Moreover, the larger the area of the light source, the softer the shadows are when rendered.
There are different approaches to rendering shadows - using shadow maps(Shadow Map), traces(Raytraced) and global illumination(Global Illumination). Let's look at them in order.
Using a shadow map allows you to get blurry shadows with unclear edges. The main Shadow Map setting is the size of the shadow map (the Size parameter in the Shadow Map Params settings rollout). If the map size is reduced, the clarity of the resulting shadows will also decrease.
The tracing method makes it possible to obtain ideally shaped shadows, which, however, look unnatural due to their sharp outline. Tracing refers to tracking the paths of individual light rays from a light source to a camera lens, taking into account their reflection from objects in the scene and refraction in transparent media. The tracing method is often used to render scenes that contain specular reflections.
Starting with 3ds Max 5, the Area Shadows method, which is based on a slightly modified tracing method, is used to obtain soft shadows. Area Shadows (Shadow distribution) allows you to calculate shadows from an object as if there was not one light source in the scene, but a group of point light sources evenly distributed in a certain area.
Although ray tracing accurately reproduces the fine detail of the generated shadows, it is not an ideal rendering solution due to the sharp outlines of the resulting shadows.
The global illumination method (Radiosity) allows you to achieve soft shadows in the final image. This method is an alternative to lighting tracing. While tracing visualizes only those areas of the scene that are illuminated by light rays, global illumination calculates the scattering of light in unlit or shadowed areas of the scene based on an analysis of each pixel in the image. This takes into account all reflections of light rays in the scene.

ADVICE
Global illumination can produce realistic images, but the rendering process is very taxing on the workstation and also takes a long time. Therefore, in some cases it makes sense to use a lighting system that simulates the effect of diffused light. In this case, light sources must be placed in such a way that their position coincides with the places of direct light exposure. Such sources should not create shadows and should have low brightness. This method certainly does not produce as realistic an image as can be obtained using a true global illumination method. However, in scenes that have simple geometry, it can be quite useful.

There are several algorithms for calculating global illumination; one of the methods for calculating reflected light is Photon Mapping. This method involves calculating global illumination based on creating a so-called photon map. Photon map represents scene illuminance information collected using tracing.
The advantage of the photon tracing method is that once saved as a photon map, the photon tracing results can later be used to create global illumination effects in 3D animation scenes. The quality of global illumination calculated using photon tracing depends on the number of photons, as well as the tracing depth. Using photon tracing, you can also calculate the caustic effect.

The 3dsMax environment offers us several light sources (ILs) that work correctly with the standard Scanline Default Renderer. They all differ in the way light is emitted and, secondarily, in the shape of the cast shadow. They can be used to simulate almost any lighting scheme available in the real world. All standard ICs available in 3dsMax replicate the properties of sources found in our lives. Currently available in 3dsMax: Target Spot, Free Spot, Target Direct, Free Direct, Omni, SkyLight.

You can create any of these sources as follows.

Go to the Create panel.
Select the Lights category.
In the drop-down list, define the source type as Standart.
Select the desired IS.

mr Area Omni and mr Area Spot sources work correctly only with the Mental Ray visualizer.

So what are these sources?

Target Spot and Free Spot

A Spot light source simulates the propagation of light by a focused beam. We can observe similar behavior in a searchlight, beacon, flashlight, car headlights, etc.

Fig. 1 Light distribution and shadow shape at a Spot type source

Since the emitted rays of light diverge from the point of radiation at an angle, the shadow cast by this source increases in area as it moves away from the object. It is logical to assume that such an IC is not applicable for simulating sunlight, but is well suited for artificial ICs. In rare cases, it is possible to partially imitate natural effects - for example, the passage of sunlight through gaps in the clouds or through foliage in the forest (Fig. 2, top right).

Fig.2 Examples of real light beams

Target Direct and Free Direct

A Direct light source simulates the propagation of parallel rays. Light is emitted not from a point, as is the case with the Spot IC, but from a plane. In nature, the source of parallel rays is the sun. Such a source allows shadows to be cast on objects in the form of elongated projections without expanding them as they move away from the object.

Fig. 3 Light distribution and shadow shape at a Direct type source

Omni emits light from a point in all possible directions. Shadows from objects exposed to Omni radiation resemble the shape of Spot shadows. These are projections that expand with distance from the object. With Omni we can imitate light from candles, various lamps, ball lightning etc.

Fig.4 Light distribution and shadow shape at an Omni type source

Fig.5 Examples of point light sources

Skylight

Imagine a giant dome over your scene in 3dsMax with light emanating from the surface. The rays are repeatedly reflected from objects and eventually fade, losing energy. Comprehensive illumination with multiple reflections.

Fig.6 Light distribution and shadow shape at a Skylight source

As a result, we get an even lighting picture and soft shadows (Fig. 7). This is exactly how Skylight works. Such lighting is often self-sufficient and does not require additional ICs. This lighting method eliminates black gaps in the shadows, and therefore loss of detail.

Fig.7 Soft shadows under Skylight lighting

Standard visualizer = low quality?

It would be a mistake to think that the Default Scanline Renderer (DSR) is a stone age and Vray, Mental Ray, Final Render, Brazil, etc. renderers are used everywhere. You will be surprised, but many tasks are solved by the standard renderer of the package (in the case of 3dsMax, this is DSR). For example, the footage for the “Ship Crash” video was rendered using ordinary DSR.

Fig.8 Visualization frames of the fall of a downed plane

Therefore, you should not think that you cannot get beautiful light using a standard visualizer and standard lighting sources. In the end, the light is set by the artist, not the visualization program.

Fig.9 Visualization using Default Scanline Renderer

Light Source Settings

Spot and Direct (Target and Free).

Fig. 10 shows scrolls of IC settings (they can be found if you go to the Modify palette, having first selected the IC).

Fig.10 Light source settings (Spot,Direct)

Scroll
General Parameters

Enable/disable light source
Change IP type (Spot, Direct, Omni)
Enable/disable target marker (active for Spot/Direct)
Distance from IS to target marker
Enable/disable shadow rendering for this IP
Use/don't use global shadow settings
If disabled, a special type of shadow can be used for this IC. If enabled, then all IPs in the scene will have the same type of shadows
Shadow type (Advanced ray-traced shadows, Area shadows, Ray-traced shadows, Shadow maps)
In the second part more details about each type
Calls up a window where you can exclude objects from the IS influence zone

Intensity/Color/Attenuation

IS intensity
Light color tone
Fade Type (None, Inverse, Inverse Square)
The distance at which the light begins to fade
Show the attenuation “lens” (even when the IC is inactive). Helps visually assess the attenuation limit
Parameters of “near” attenuation. Use - enable. Show - show the attenuation “lenses”. Start/End - boundaries, beginning and end of attenuation
Far attenuation parameters

Advanced Effects

Allows you to set the contrast between areas of light and shadow
Allows you to smooth the boundary between areas of light and shadow
Enable/disable IC diffuse lighting
Enable/disable glare from IC
Enable/disable ambient lighting
You can add a map to simulate a complex beam shape. For example, passing through a grate or foliage. Check mark opposite: enable/disable effect

Spotlight/Directional Parameters

Show cone/cylinder of light propagation (even if IC is not selected)
Increase the area of light distribution. Allows you to get rid of the light spot
Size of the “hot spot” - inner cone/cylinder
Outer cone/cylinder size
For Spotlight - angles of light emission in degrees. For Directional - radii in units of measurement, for example in mm. The more the dimensions of the outer and inner cone/cylinder differ, the more blurred the light spot is.
Cross-sectional shape of light cone/cylinder
Aspect - proportions of the rectangular section of the cone/cylinder (default 1 - square section). The aspect can be adjusted using the loaded map

Shadow Parameters

Shadow color
Density - shadow density. Value 1 - maximum opacity
On - allows you to use the card (item 4)
The color of the added card is mixed with the color of the shadow
On - allows you to mix the color of the light with the color (or colors if the map is enabled) of the shadow
Enabling this option allows atmospheric effects to cast shadows
Shadow opacity (default 100)
Mixing an atmospheric color with a shadow color

Atmospheres & Effects

Allows you to add effects related to IP
Removes added effects
List of added effects
Opening the settings window for the selected effect

Omni

Parameter scrolls are similar. The only thing missing is the Spotlight/Directional Parameters rollout, since the Omni IC does not have a propagation cone or cylinder.

Skylight

The Skylight light source has unique parameters, although it only has one scroll.

Enable/disable IS
Light intensity (brightness)
Use the same color as the dome color that is set in the global environment settings (Rendering -> Environment...)
Use your special dome color
Dome color
Activate the card (step 8)
If less than 100, then the map colors are mixed with the Sky Color dome color
Set map (HDR recommended)
Enable/disable shadow casting
The number of rays per sample - adjusts the quality of shadow rendering. The more, the better. For animation this value should be quite high (>30) to avoid flickering
. A value of zero indicates that the shadow is not separated from the object (except, of course, when the object is levitated)

Lighting in 3dsMax. Part 2: Setting up shadows

Among the standard light sources, three sources (namely Spot, Direct and Omni) allow us to choose the type of shadows to be calculated. If we use the standard Default Scanline Renderer (DSR), then the following will be of interest to us: Advanced ray-traced shadows, Area shadows, Ray-traced shadows, Shadow maps.

When you select a shadow type among the IS parameters scrolls, a shadow parameters scroll appears, the name of which begins with the name of the type.

Shadow Map

The simplest and most undemanding type of shadows in terms of computational resources.

Distance of object from cast shadow
The size of the map based on which the shadow is calculated. The larger the map, the better the quality of the calculated shadow. It is better to use numbers of order 2n
Blurring the shadow edge. Increasing the parameter allows you to get rid of the jagged edge of the edge when the map resolution is low
Parameter responsible for controlling the Bias value. Disabled by default (best result in most cases). In the case of animation, enabling the option
If disabled, light passes through the surface if it hits polygons with normals facing away from it. Enabling this option allows you to get correct shadows

In Fig. 1, the top row of images clearly shows the change in shadow quality as the Size parameter increases. Even a significant increase in the size of the map does not solve the problem of jagged edges of the shadow, although the shadow pattern certainly becomes more detailed.

In the second row, in all three cases the map size remains the same, but the Sample Range parameter changes. By gradually increasing it, we got rid of the jaggedness, blurring the edge of the shadow.

Fig.1 Changing the quality of the shadow of the Shadow Map type with various parameters

Ray-Traced Shadows

This type of shadow is calculated based on a tracing algorithm. They have clear edges and are practically impossible to customize.

Ray-Traced Shadow is more accurate relative to Shadow Map. In addition, it is able to take into account the transparency of the object, but at the same time it is “dry” and clear, which does not look very natural in most cases. Ray-Traced Shadow is more demanding on computer resources than Shadow Map.

Distance of object from cast shadow
Tracing depth is a parameter responsible for developing the shadow. Increasing this value can significantly increase rendering time

Ray-Traced Shadows with an Omni type IC will take longer to render than a combination of Ray-Traced Shadows + Spot (or Directional)

Fig.2 Ray-Traced Shadows from opaque and transparent objects

Advanced Ray-Traced Shadows

Shadows of this type are very similar to Ray-Traced Shadows, but as the name implies, they have more advanced settings that allow for more natural and correct calculations.

Shadow generation method
Simple- a single beam emerges from the IC. The shadow does not support any anti-aliasing or quality settings
1-Pass Antialias- the emission of a beam of rays is simulated. Moreover, the same number of rays is reflected from each illuminated surface (the number of rays is adjusted by Shadow Quality).
2-Pass Antialias- Similar, but two beams of rays are emitted.
If turned off, then light passes through the surface if it hits polygons with normals facing away from it. Enabling this option allows you to get correct shadows
Number of rays emitted by an illuminated surface
The number of secondary rays emitted by the illuminated surface
The radius (in pixels) of the shadow edge blur. Increasing the parameter improves the quality of the blur. If small details are lost when blurring the edge, correct this by increasing Shadow Integrity
Distance of object from cast shadow
A parameter that controls the randomness of rays. Initially, the rays are directed along a strict grid, which can cause unpleasant artifacts. Introducing chaos will make the shadow look more natural
Recommended values are 0.5-1.0. But blurrier shadows will require a higher Jitter Amount

Area Shadows

This type of shadow allows you to take into account the dimensions of the light source, so you can get natural extended shadows that “split” and blur as you move away from the object. 3dsMax produces these shadows by mixing a number of “samples” of shadows. The more “samples” and the better the mixing, the better the calculated shadow.

The shape of an imaginary light source that allows you to determine the nature of the shadow.
Simple- a single beam emerges from the IC. The shadow does not support any anti-aliasing or quality settings.
Rectangle Light- simulates the emission of light from a rectangular area.
Disc Light- The IC behaves as if it had acquired the shape of a disk.
Box Light- imitation of cubic IC.
Sphere Light- imitation of a spherical IC.
If disabled, light passes through the surface if it hits polygons with normals facing away from it. Enabling this option allows you to get correct shadows.
Controls the number of rays emitted (non-linear). The higher the number, the more rays, the higher the quality of the shadow.
A parameter responsible for the quality of the shadow. For rational calculation, always set the number higher than Shadow Integrity.
The radius (in pixels) of the shadow edge blur. Increasing the parameter improves the quality of the blur. If small details are lost when blurring the edge, correct this by increasing Shadow Integrity.
The distance of the object from the cast shadow.
A parameter that controls the randomness of rays. Initially, the rays are directed along a strict grid, which can cause unpleasant artifacts. Introducing chaos will make the shadow look more natural.
Dimensions of the imaginary source. Length - length, Width - width, Height (active only for Box Light and Sphere Light) - height.

Let's take a look at Fig.3. On the first fragment. Several shadow "samples" are superimposed on each other without any blending. In the second fragment they are already mixed (Jitter Amount changed from 0.0 to 6.0). Mixed “samples” are perceived as a more natural shadow, but its quality leaves much to be desired. The third fragment shows a shadow with excellent quality (Shadow Integrity and Shadow Quality changed from single values to 8 and 10, respectively).

Second row in Fig. 3. illustrates how the character of the shadow changes if we increase the size of the imaginary source. In this case, we have an imaginary source of the Rectangle Light type (flat rectangular). As the source area increases, the shadow blur increases.

Fig.3 Changing the quality of the Area Shadow type shadow with different parameters

Some parameter values are advisory in nature, but everything is limited only by your imagination. The best way to figure it out is through experimentation. Don't be afraid to experiment with light. Catch the mood of the future picture and give in to the settings.

In Fig.4. chess knight with a material based on a simple procedural Wood texture. Three light sources tinted in different colors. Simple setup, but the figure looks good nonetheless.

Fig.4 Chess piece “Knight”. Subject visualization

Resume

Lighting is one of the most important stages in working on a three-dimensional scene. At first glance, it may seem that the dry information of the lesson cannot be applied to creative work. However, with the proper ingenuity and hard work, you can achieve incredible results. After all, all digital images are just collections of ones and zeroes, and 3dsMax is just another tool for you, just like a pencil or brush.

V-Ray is one of the most popular plugins for creating photorealistic renderings. Its distinctive feature is ease of setup and the ability to obtain high-quality results. Using V-Ray in 3ds Max, you create materials, lighting, and cameras that interact in a scene to quickly create a naturalistic image.

In this article we will explore lighting settings using V-Ray. The right light is very important to create a visualization correctly. It should bring out all the best qualities of objects in the scene, create natural shadows and provide protection from noise, overexposure and other artifacts. Let's look at the V-Ray tools for adjusting lighting.

1. First of all, download and install V-Ray. We go to the developer’s website and select the version of V-Ray designed for 3ds Max. Let's download it. In order to download the program, register on the site.

2. Install the program following the prompts of the installation wizard.

3. Launch 3ds Max, press the F10 key. Here is the render settings panel. On the “Common” tab, find the “Assign Renderer” rollout and select V-Ray. Click “Save as defaults”.

Lighting comes in different types depending on the features of the scene. Of course, the lighting for object rendering will be different from the lighting settings for the exterior. Let's look at several basic lighting schemes.

Setting up light for exterior rendering

1. Open the scene in which the lighting will be adjusted.

2. Set up the light source. We will imitate the sun. In the Create tab of the toolbar, select Lights and click V-Ray Sun.

3. Specify the starting and ending points of the sun's rays. The angle between the beam and the earth's surface will determine the morning, afternoon or evening type of atmosphere.

4. Select the sun and go to the "Modify" tab. We are interested in the following parameters:

— Enabled — turns the sun on and off.

— Turbidity — the higher this value, the more dusty the atmosphere.

— Intensity multiplier — a parameter that regulates the brightness of sunlight.

— Size multiplier — the size of the sun. The higher the parameter, the more blurry the shadows will be.

— Shadow subdivs — the higher this number, the better the quality of the shadows.

5. This completes the sun setup. Let's adjust the sky to make it more realistic. Press the "8" key and the environment panel will open. Select the DefaultVraySky map as the environment map as shown in the screenshot.

6. Without closing the environment panel, press the "M" key to open the material editor. Drag the DefaultVraySky map from the slot in the environment panel into the material editor while holding down the left mouse button.

7. Edit the sky map in the material browser. After selecting the map, check the “Specify sun node” checkbox. Click "None" in the "Sun light" field and click on the sun in the model view. We have just connected the sun and the sky. Now the position of the sun will determine the brightness of the sky, completely simulating the state of the atmosphere at any time of the day. We will leave the remaining settings as default.

8. In general terms, the exterior lighting is set. Run renders and experiment with light to achieve the effects you want.

For example, to create the atmosphere of a cloudy day, turn off the sun in its parameters and leave only the sky or HDRI map shining.

Setting up light for object visualization

1. Open a scene with a finished composition for rendering.

2. In the Create tab of the toolbar, select Lights and click V-Ray Light.

3. Click in the projection where you want to place the light source. In this example, let's place the light in front of the object.

4. Let's configure the light source parameters.

— Type — this parameter specifies the shape of the source: flat, spherical, dome. Shape is important when the light source is visible in the scene. For our case, let Plane remain the default.

— Intensity — allows you to set the color strength in lumens or relative values. We leave relative ones - they are easier to regulate. The higher the number on the Multiplier line, the brighter the light.

— Color — determines the color of the light.

— Invisible — the light source can be made invisible in the scene, but it will continue to shine.

— Sampling — the “Subdivides” parameter adjusts the quality of rendering of light and shadows. The higher the number in the line, the higher the quality.

It is better to leave the remaining parameters at default.

5. For object visualization, it is recommended to install several light sources of different sizes, illumination intensity and distance from the object. Place two more lights in the scene on either side of the subject. You can rotate them relative to the scene and adjust their parameters.

This method is not a “magic pill” for perfect lighting, but it simulates a real photo studio, and by experimenting in it, you will achieve a very high-quality result.

So, for 3D models to look natural in a rendered image, they need to be properly lit. By default, 3ds max 7 uses its own system, which evenly illuminates objects in a 3D scene. With this lighting system, there are no shadows in the final image, which looks unnatural. To make objects cast shadows, you need to add light sources to the scene. As soon as light sources appear in the scene, the lighting system used by 3ds max 7 automatically turns off.

Light sources in 3ds max 7 are divided into directional (Spot) and omnidirectional (Omni). The first category includes Target Spot, Free Spot, and mr Area Spot (used by mental ray). Omnidirectional lights include Omni and mr Area Omni (used by the mental ray renderer).

Directional lights are used primarily to illuminate a specific object or area of the scene. Using directional light sources, you can simulate, for example, the light of car headlights, the beam of a spotlight or flashlight, etc. Omnidirectional light sources emit light evenly in all directions. Using them, you can simulate, for example, lighting from electric lamps, lanterns, flame light, etc.

Regardless of which light source is used in the scene, it is characterized by such parameters as Multiplier (Brightness), Decay (Attenuation) and Shadow Map (Type of cast shadow) (Fig. 6.1). By default, the Multiplier of any light source is set to one, and the Decay option is turned off.

Since in real life light from sources obeys the laws of physics, the intensity of light propagation depends on the distance to the light source. If you want to simulate a realistic light source, you need to set the Decay function in the light source settings, which is determined by the inverse dependence of light on distance or the square of distance. The second option most accurately describes the propagation of light.

When creating scene illumination in relation to light sources, the following effects are often used.

Volume Light - The light created by the source colors the space in the color of the source. In real life, this effect can be observed in dark, dusty or smoky rooms. A beam of light breaking through the darkness is clearly visible.
Lens Effects - Reminiscent of the effect that is obtained in real life on an image when using special lenses with different lens systems. These can be highlights of various shapes, reflections, etc.

Rice. 6.1. Omni Light Source Settings

To use an effect, in the light source's Atmospheres & Effects settings rollout, click the Add button and select the desired effect in the Add Atmosphere or Effect window (Figure 6.2).

Rice. 6.2. Add Atmosphere or Effect Window

You can also add an effect to the scene by running Rendering > Environment or pressing the 8 key. In the Environment and Effects window, go to the Effects tab and then use the Add button to add one of the effects into the scene.

Rice. 6.3. Environment and Effects Window

To configure the effect, use the Setup button in the light source's Atmospheres & Effects settings rollout. This will take you to the Environment and Effects window. In order for the program to calculate the effect, you must specify in its settings which light source the selected effect is applied to. Click the Pick Light button (Fig. 6.3), and then click on the light source in the projection window.