Image Sampler (Antialiasing) - 4th lesson

Image sampler

Type - specifies the image sampler type:

Fixed - this sampler always takes the same number of samples per pixel;

Adaptive QMC - this sampler takes a variable number of samples per pixel depending on the difference in the intensity of the pixels;

Adaptive subdivision - this sampler divides the image into an adaptive grid-like structure and refines depending on the difference in pixel intensity.

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Antialiasing filter

This section allows you to choose an antialiasing filter. All standard 3ds Max filters are supported with the exception of the Plate Match filter...

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Fixed image sampler

This is the simplest image sampler, and it takes a fixed number of samples for each pixel.

Subdivs - determines number of samples per pixel. When this is set to 1, one sample at the center of each pixel is taken. If this is greater than 1, the samples are distributed within the pixel. The actual number of pixels is the square of this parameter (e.g. 4 subdivs produce 16 samples per pixel).

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Adaptive QMC sampler

This sampler makes a variable number of samples per pixel based on the difference in intensity between the pixel and its neighbors. 

This is the preferred sampler for images with lots of small details and/or blurry effects (DOF, motion blur, glossy reflections etc). It also takes up less RAM than the Adaptive subdivision sampler.


Min subdivs - determines the initial (minimum) number of samples taken for each pixel. You will rarely need to set this to more than 1, except if you have very thin lines that are not captured correctly, or fast moving objects if you use motion blur. The actual number of pixels is the square of this number (e.g. 4 subdivs produce 16 samples per pixel).

Max subdivs - determines the maximum number of samples for a pixel. The actual maximum number of sampler is the square of this number (e.g. 4 subdivs produces a maximum of 16 samples). Note that V-Ray may take less than the maximum number of samples, if the difference in intensity of the neighbouring pixels is small enough.

Use QMC sampler threshold - when this is on (the default), V-Ray will use the threshold specified in the QMC sampler to determine if more samples are needed for a pixel. When this is off, the Color threshold parameter will be used instead.

Color threshold - the threshold that will be used to determine if a pixel needs more samples. This is ignored if the Use QMC sampler threshold option is on.

Show samples - if this is on, V-Ray will show an image where the pixel brightness is directly proportional to the number of samples taken at this pixel. This is useful for fine-tuning the antialiasing of the image.

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Adaptive subdivision sampler

 This is an advanced image sampler capable of undersampling (taking less than one sample per pixel). In the absence of blurry effects (direct GI, DOF, glossy reflection/reftaction etc) this is the best preferred image sampler in V-Ray. On average it takes fewer samples (and thus less time) to achieve the same image quality as the other image samplers. However, with detailed textures and/or blurry effects, it can be slower and produce worse results than the other two methods.

**Also note that this sampler takes up more RAM than the other two samplers.

Min. rate - controls minimum number of samples per pixel. A value of zero means one sample per pixel; -1 means one sample every two pixels; -2 means one sample every 4 pixels etc.

Max. rate - controls maximum number of samples per pixel; zero means one sample per pixel, 1 means four samples, 2 means eight samples etc.

Color threshold - determines the sensitivity of the sampler to changes in pixel intensity. Lower values will produce better results, while higher values will be faster, but may leave some areas of similar intensity undersampled.

Randomize samples - displaces the samples slightly to produce better antialiasing of nearly horizontal or vertical lines.

Object outline - this will cause the image sampler to always supersample object edges (regardless of whether they actually need to be supersampled). This option has no effect if DOF or motion blur is enabled.

Normal threshold - this will supersample areas with sharply varying normals. This option has no effect if DOF or motion blur is enabled.

Show samples - if this is on, V-Ray will show an image where the pixel brightness is directly proportional to the number of samples taken at this pixel. This is useful for fine-tuning the antialiasing of the image.

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Global switches - 3rd lesson

in the name of allah ...

i finished right now two lessons and this will be the third god willing ...

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Global switches

Displacement - enables (default) or disables V-Ray's own displacement mapping. Note that this has no effect on standard Max displacement mapping, which can be controlled via the corresponding parameter in the Render Scene dialog.

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Lights - enables or disables lights globally. Note that if you uncheck this, V-Ray will use the default lights. If you do not want any direct lighting in your scene, you must uncheck both this and the Default lights parameters.

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Default lights - enables or disables the usage of the default lights when there are no light objects in the scene or when you have disabled lighting globally

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Hidden lights - enables or disables the usage of hidden lights. When this is checked, lights are rendered regardless of whether they are hidden or not. When this option is off, any lights that are hidden for any reason (either explicitly or by type) will not be included in the rendering.

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Shadows - enables or disables shadows globally.

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Show GI only - when this option is on, direct lighting will not be included in the final rendering. Note that lights will still be considered for GI calculations, however in the end only the indirect lighting will be shown.

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Reflection/refraction - enables or disables the calculation of reflections and refractions in V-Ray maps and materials.

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Max depth - enables the user to limit globally the reflection/refraction depth. When this is unchecked, the depth is controlled locally by the materials/maps. When this option is checked, all materials and maps use the depth specified here.

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Maps - enables or disables texture maps.

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Filter maps - enables or disables texture map filtering. When enabled, the depth is controlled locally by the settings of the texture maps. When disabled, no filtering is performed.

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Max. transp levels - this controls to what depth transparent objects will be traced.

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Transp. cutoff - this controls when tracing of transparent objects will be stopped. If the accumulated transparency of a ray is below this threshold, no further tracing will be performed.

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Override mtl - this option allows the user to override the scene materials when rendering. All objects will be rendered with the chosen material, if one is selected, or with their default wireframe materials if no material is specified.

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Glossy effects - this option allows the user to replace all glossy reflections in the scene with non-glossy ones; useful for test renderings.

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Don't render final image - when this option is on, V-Ray will only calculate the relevant global illumination maps (photon maps, light maps, irradiance maps). This is a useful option if you are calculating maps for a fly-through animation.

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Secondary rays bias - a small positive offset that will be applied to all secondary rays; this can be used if you have overlapping faces in the scene to avoid the black splotches that may appear.

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so, i finished this lesson, i know it's almost boring but it needs to be tried by you yourself so you can observe the meaning of each parameter ...

hope you make use of the lesson...

comments are welcome ...

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v-ray frame buffer - 2nd lesson

in the name of allah ...

this will be the second v-ray lesson in this series ...

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v-ray frame buffer

Show last VFB - If you have rendered to the V-Ray VFB, but have closed it, this button allows you to open it again. The same can also be achieved with the showLastVFB ...

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Enable built-in frame buffer - Enables the use of built-in V-Ray frame buffer. Due to technical reasons, the original 3ds Max frame buffer still exists and is being created. However, when this feature is turned on - V-Ray will not render any data to the 3ds Max frame buffer. In order to preserve memory consumption we recommend that you set the original 3ds Max resolution to a very low value (like 100x100) and turn off the 3ds Max Virtual Frame Buffer from the common 3ds Max render settings ...

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Render to memory frame buffer - this will create a V-Ray frame buffer and will use it to store color data that you can observe while rendering and afterwards. If you wish to render really high resolutions that would not fit into memory or that may eat up a lot of your RAM not allowing for the scene to render properly - you can turn this feature off and use only Render to V-Ray raw image file feature ...

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Get resolution from 3ds Max - this will cause the V-Ray VFB to take its resolution from the 3ds Max common render settings ...

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Output resolution - this is the resolution that you wish to use with the V-Ray frame buffer ...

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Pixel aspect - specifies the pixel aspect for the rendered image in the V-Ray frame buffer ...

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Render to V-Ray image file - when this is on, V-Ray directly writes to disk the raw image data as it is being rendered. It does not store any data in the RAM, so this feature is very handy when rendering huge resolutions for preserving memory. If you wish to see what is being rendered, you can turn on the Generate preview setting. You can specify either a .vrimg or an .exr file for output ...

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Generate preview - this will create a small preview of what is being rendered. If you are not using the V-Ray memory frame buffer for conserving memory (i.e. Render to memory frame buffer is off), you can use this feature to see a small image of what is being actually rendered and stop the renderer if there is anything that looks wrong ...

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Save separate render channels - this option allows you to save the channels from the VFB into separate files. Use the Browse... button to specify the file. This option is available only when rendering to a memory frame buffer. If rendering is done only to a raw image file, the render channels can be extracted from that file after rendering is complete ...

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Save RGB and Save Alpha - these options allow you to disable saving of the RGB and Alpha channels respectively. This can be useful if you only want to generate other render channels. Note that V-Ray will still generate the RGB and Alpha channels, however they will not be saved ...

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that was a brief explaining to the frame buffer features wish u make use of it ...

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1st lesson - about V-ray

this is the first lesson in this category ...


V-Ray is a renderer plugin for 3ds Max. In order to use V-Ray, you must first select it as your current renderer. You can do that by clicking on the Assign... button in the Current renderers rollout of the Render Scene dialog ...



In 3ds Max 9 and later, the V-Ray parameters are divided into several tabs in the render scene dialog additionally each tab is divided into several rollouts ...

more detailed description of each rollout will be explained later God willing ...

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