Render SettingsΒΆ

The render settings include a lot of parameters to globally control your render.

Samples

The maximum number of rays to be shot per pixel.

BrdfSamples

Adaptive Threshold

The noise threshold below which the renderer stops sampling a pixel.

The Adaptive Threshold controls the final pixel noise quantity. Using Adaptive Sampling allows the renderer to shoot more samples where the noise is higher, while shooting less samples where the noise is lower. Compared to non adaptive sampling, this usually results in a uniform noise quality over the image, and much faster renders for a given quality threshold.

The left image uses Samples = 40 and Adaptive Threshold = 0, the right image uses Samples = 1024 and Adaptive Threshold = 0.05, with equivalent render times. You can remark that the non adaptive render has large differences in noise quality, with bokeh being visibly subsampled, a few fireflies and the non blurred part nearly noise free. On the other hand, the adaptive render has a very uniform noise. Achieving this bokeh quality without adaptive sampling would have required 1024 samples per pixels on the whole image, which is a waste of computation for the areas which would not require that amount of samples!

The Confidence AOV shows the noise quantities for both renders (darker areas have less noise, brighter areas have more noise.)

Apart from bokehs, the adaptive error is quite uniform compared to the non adaptive error.

The Heat AOV indicates the number of samples shot per pixel (blue pixels have lower samples, white pixels have the maximum number of samples.)

AdaptiveThreshold

Adaptive Min Samples

The minimum number of rays to shoot per pixel.

This value controls the minimum number of rays to shot per pixel before the adaptive sampling is evaluated. In some cases, like in very occluded parts of the scene or on caustics, the adaptive sampling can miss some features of the image, and it can be necessary to increase this in order for the sampler to see these features. Rendering in adaptive with buckets and high threshold may exhibit this issue, and you should increase the minimum number of samples.

Increase the minimum samples from 2 to 8 to fix the motion blur broken trail.

AdaptiveMinSamples

Sampling Mode

Switch between progressive and bucketed rendering modes.

  • "Progressive" renders the full image iteratively, enabling a quick preview of the whole image, and progressively refining up to the final quality.
  • "Bucket" renders the image by buckets. Each bucket is sampled up to the final quality until another bucket is rendered.

Note that rendering deep images requires switching to the Bucket mode.

SamplingMode

Path Guiding

Toggle path guiding rendering mode. "Path Guiding" renders the full image iteratively in several passes, where each pass uses info gathered during the previous pass about incident light direction. On difficult scenes, after a few passes, image can converge significantly faster than with unguided sampling.

PathGuiding

Size

Use Project Settings

Connects the image settings to the project settings, see Preferences > Project Settings.

Width

Width of the image, in pixels.

Height

Height of the image, in pixels.

Aspect Ratio

Aspect ratio of the image.

The aspect ratio set to 1.0, 0.5 and 2.

AspectRatio

File

Write Images

Writes the images of the pass during a local render (CTRL+R or "Local" render). During a batch or a farm render, the images are always written.

WriteImages

File Pattern

Pattern used to create the name of the output file. The pattern can contain $# items which are replaced by the following:

  • $l is the RenderPass path (including prefix and hierarchy)
  • $L is the RenderPass name (excluding prefix and hierarchy)
  • $n is the RenderLayer name
  • $o is the Output name
  • $e is the eye number (1 for the leftmost)
  • $E is the eye name (as 'left' and 'right')
  • $c is the camera name including prefix
  • $C is the camera name excluding prefix
  • $x is the default display extension (exr, tiff, etc.)
  • $f is the frame number ($03f is frame number 0-padded to 3 digits)
File naming

File

Preview of the final filename in wip mode, for the first output, frame 666 and the eye #1.

FileName

Layer Pattern

Pattern used to create the name of the layer inside the file, when supported. When rendering in exr files or supported formats with layering, this value is used to control the name of the produced layers. You can use specifiers like $f, $e, $x, etc, like in $l_$n_$o. The default value is $n_$o. File naming

FileLayerName

File Format

The file format of the output image.

  • Tiff : write a tiff file. This format support 8 bits and float pixels. It applies a gzip like lossless compression.
  • Targa : write a Truevision TGA file. This format support the 8 bits pixels. It is not compressed.
  • Png : write a Portable Network Graphcis PNG image. This format support the 8 bits pixels. It applies a gzip like lossless compression.
  • OpenEXR : write an OpenEXR file. This format supports the half float and float pixels, layers and deep images. It includes various compression schemes.
  • OpenEXR/Id : write an OpenEXR/Id file. This format supports the half float pixels. A dedicated reader is needed to read the image in the compositing software. Using this format, one can isolate any object in the image.

DisplayDriver

Use LPEs

Write a deep OpenEXR/Id with LPEs (light path expressions)

Write Deep Image

Write a deep image. A deep image contains multiple pixel colors in depth. Only for the OpenEXR format. Those images can be very large if not carefully compressed. Wikipedia Deep image compositing

DeepImage

Deep Image Compression Ratio

Controls the lossy compression of the deep pixels. 0 means no compression, 1 means maximum compression. In all cases, the result of the flatten image is lossless. Only for the OpenEXR format in Deep Image mode.

DeepCompression

Deep Image Merge Flag

Allow to merge the fragments from different objects in the same deep fragment.

DeepMerge

Multi Part

If checked, writes the AOVs as OpenEXR 2.0 multi-part files. If not checked, writes the AOVs as channels (compatible with OpenEXR 1.0). Only for the OpenEXR format.

MultiPart

Meta Data

The meta data to insert in the EXR file header. You can add a metadata per line. Here is an exemple of two meta data :
key1=value1
key2=value2

MetaData

Pixel Format

Pixel format of the image.

  • RGBA : the red, green, blue and alpha channels are written in the file.
  • RGB : the red, green, blue channels are written in the file.
  • A : the alpha channel is written in the file.

PixelFormat

Depth

Bit depth of the image.

  • 8 bits : the color components are quantized on 256 values. This produces the smallest files, with the smallest color precision. The color values are clamped between [0.0, 1.0]. 8 bits colors should be written using a sRGB gamma.
  • Half float : the components are stored in a half float (16 bits) which is a good choice for the color channels. No clamping. Only for the OpenEXR format. This mode is not precise enough for texture coordinates (st), positions (P) and depth (Z) AOVs, choose Float for those.
  • Float : the components are stored in a float (32 bits) which is the highest quality you can get. No clamping. Only for the OpenEXR and Tiff formats.

Depth

Compression method

The OpenEXR compression algorithm.

  • None: no compression.
  • RLE: run length encoding.
  • Zips Lines: zlib compression, one scan line at a time.
  • Zips Blocks: zlib compression, in blocks of 16 scan lines. The default compression method.
  • Piz: piz-based wavelet compression.
  • PXR24: lossy 24-bit float compression.
  • B44: lossy 4-by-4 pixel block compression, fixed compression rate.
  • B44A: lossy 4-by-4 pixel block compression, flat fields are compressed more.
  • DWAA: lossy DWA A compression method.
  • DWAB: lossy DWA B compression method.

Compression

DWA Compression

Higher values provide more compression of the final image file, but reduce the quality. Only for EXR DWAA and DWAB compresion methods.

OpenEXRId Pattern

This attribute set the naming scheme of objects in the OpenEXRId file, using tokens such as $(PATH) and $(TAGS).

File Alpha Mode

Indicate if the colors are written multiplied by the opacity in the file. In all cases, the alpha channel is written with the opacity left untouched.

  • Unpremult/Unassociated Alpha : Write color independently of the opacity.
  • Premult/Associated Alpha : Write color with the opacity multiplied.

ColorMode

Gamma

Indicate the LUT to apply to the output image. The default value uses the project's gamma. For 8 bits images, you may want to use a sRGB gamma. For a float or a half float image, you may want to save it in the linear color space, i-e a gamma or 1.0.

Backup Project File Name

The name of the backup gproject file to be saved along rendered images. When rendering images in batch or farm, Guerilla can save a file along with each active Layer. This option is useful if you want to keep a track of the setup that is the source of the rendered image. This value accepts $l and $n specifiers. When left empty, no file is saved. File naming

BackupProjectFileName

Image Sampling

Time Jitter

If checked, change the jitter pattern at every frame.

Motion Blur

Globally enable or disable the motion blur. This flag completely enables/disables the rendering of motion blur. Note that disabling motion blur also disables motion vectors. To disable motion blur but keep the motion vectors information, use the Instantaneous motion blur density instead.

Motion Blur Density

Change the shape of the motion blur.

The motion blur density set to Uniform, Triangle, Leading, Trailing and Gaussian.

The Instantaneous density samples the time at a single instant between the shutter opening and closing. You can change this time using the Motion Blur Parameter, with 0 being shutter opening, and 1 being shutter closing.

The Trapeze density samples the time using a parametric trapezoidal density, using Motion Blur Parameter as the shutter opening and closing speed. 0 is the slowest, which stretches the trapeze to a triangle density, while 1 is the quickest, which stretches the trapeze to a uniform density.

To disable motion blur, you should consider using the Instantaneous density, as this preserves useful information such as motion vectors through the whole rendering pipeline.

Motion Blur Trails

The motion blur trail density, 0 for smooth trails, 1 for sharp trails.

Motion Blur Time

The instant time in the frame for Instantaneous distribution (0 for shutter open, 1 for shutter close.)

Motion Blur Width

For Trapeze density, the width of the fully opened shutter plateau

Motion Blur Width

For Parametric density, the width of the fully opened shutter plateau

Motion Blur Skew

For Parametric density, skews the distribution trapeze toward shutter open (0) or towards shutter close (1)

Motion Blur Shape

For Parametric density, change the density trails shape, from smooth (0) to sharp (1)

Depth of Field

Enables simulating the depth of field lens effect.

Bokeh Bitmap

Specifies the bokeh luminance bitmap used to control the bokeh distribution.

Bokeh Sides

Specifies the number of sides of the parametric bokeh. Values below 3 use a simple round bokeh.

Bokeh Angle

Specifies the tilting of the parametric bokeh.

Bokeh Inner Density

Specifies the density of the parametric bokeh at the center.

Bokeh Outer Density

Specifies the density of the parametric bokeh at the edge.

Bokeh Roundness

Specifies the roundness of the parametric bokeh, positive values for a round bokeh, 0 for polygonal and negative for a pointy bokeh.

Pixel Filter

Filter

The filter to use to reconstruct the final image.

A test image using the selected filter. Watch the black and white checker for the antialiazing quality, the multi color hairs for the sharpness and the bright sphere for the ringing.

Box Triangle Gaussian Mitchell Custom Mitchell Sinc BSpline Catmull-Rom

Note that rendering deep images requires a FIS filter mode, such as Triangle FIS.

X Width

Width of the filter, in pixels. 1 is the ideal size regardless the filter type. A value larger than 1 will blur the image, a value smaller than 1 will produce a sharper image.

Y Width

Height of the filter, in pixels. 1 is the ideal size regardless the filter type. A value larger than 1 will blur the image, a value smaller than 1 will produce a sharper image.

Path Throughput Clamp

Clamp the light path samples values.

Clamp Pre Filter

Clamp the sample values. Try [0,10] or [0,5] to remove fireflies. If both values are equal, no clamping is done.

Clamp Post Filter

Clamp the pixel values. If you want to output positions, normals or any other non ranged values, you should reduce the min value to a negative value (like -10000). Set range minimum to 0 to avoid negative values in colors, due to ringing filters, for instance.

Mitchell Parameters

Mitchell filter B and C parameters.

Shading

Max Bounces

Global maximum raytracing depth. This value clamps the value contained in raytracing nodes.

Max Bounces set to 0, 1 and 2.

TraceDepth

Light Max

Maximum depth for light

This value controls the photon tracing depth globally. Set to 0 to disable bidirectional path tracing. Increase this above 0 to turn on bidirectional path tracing.

LightTraceDepth

Diffuse Bounces

Maximum number of diffuse bounces. This value can be individually overriden in the shader properties.

Diffuse Bounces set to 0, 1 and 2.

DiffuseDepth

Specular Bounces

Maximum number of specular bounces. This value can be individually overriden in the shader properties.

Specular Bounces set to 0, 1 and 2.

SpecularDepth

Refraction Bounces

Maximum number of refraction bounces. This value can be individually overriden in the shader properties.

Refraction Bounces set to 0, 1 and 2.

RefractionDepth

Volume Bounces

Maximum number of bounces in volumes. This value can be individually overriden in the shader properties.

Volume Bounces set to 0, 1 and 2.

VolumeDepth

Shading Blurriness

Control the shading blurriness, in pixel area.

Smaller values mean finer texture lookups but greater memory usage.

ShadingBlurriness

Russian Roulette

Control the russian roulette cutoff.

The russian roulette randomly stops the light path propagation, based on the surface reflectivity or transmitivity. This reduces the average light path length, resulting in lower rendering time for the sample amount of samples per pixel, but usually increases the noise.

Left with Russian Roulette set to 0.0 and right set to 1.0 (half rendering time), with fixed 16 samples per pixel and 8 bounces.

While enabling the russian roulette usually requires more samples, this generally proves a good trade off in render time, especially when you increase the bounces limits.

Left with Russian Roulette set to 0.0 and right set to 1.0 (0.6x rendering time), with identical Adaptive Threshold and 8 bounces.

Higher albedos are less affected by the russian roulette, and surfaces with albedo equal or greater than 1 (e.g. pure red or white ...) disable the russian roulette.

RussianRoulette

Light Color

General light color This parameter adjusts globally all lights (and emission) color.

LightColor

Light Intensity

General light intensity This parameter adjusts globally all lights (and emission) intensity.

LightIntensity

Light Exponent

General light exponent This parameter adjusts globally all lights (and emission) exponent.

LightExponent

Light Cut-Off

Minimum amount of light to be accumulated from lights Below this threshold light is cut off. This option prevents too small values from being traced and accumulated, and reduces the number of shadow rays. Increasing this value too much will remove visible light.

LightCutOff

Light Sampling Mode

Light sampling algorithm. ADD DOC HERE.

Spectral

Enable spectral rendering

Using spectral rendering allows rendering more accurately certain effects such as dispersive refractions.

Refraction without and with spectral rendering

Note that spectral rendering is not enabled by default on all shaders and most notably, Surface2 > Dispersion must be increased to fully effect the spectral effect in refractions.

Spectral

Adaptive Luma Threshold

Controls the low luma threshold below which the adaptive stops sampling

AdaptiveLumaThreshold

Caustic Blur

Controls the caustic paths blurring

Higher caustic blur results in less noisy images, but can alter the shape and intensity of caustics, while lower caustic blur results in more acurrate caustics, at the cost of noise and fireflies.

Caustic blur set to 1.0, 0.2 (1.6x render time) and 0.05 (2.5x render time)

CausticBlur

Caustics Type

Controls which light paths are to be considered caustics

CausticsType

Caustic Buffer

Enable the caustic buffer. Rendering caustics using bidirectional path tracing requires caustics generated by light paths to be stored separately in a distinct image buffer. Enable this to benefit from light paths caustics.

DirectCamera

Stereoscopy

Stereo Viewpoints

One Pass Stereo

Enables stereoscopic viewpoints to be rendered in one single pass. If checked, allows to render all viewpoints in one single pass. If unchecked, forces to render all viewpoints separately.

Force Eye

Force the rendering of a single eye.

Denoising

Denoiser

The denoiser to use. If "None", no denoising. "Default" is an internal experimental denoiser.

Altus Command Line.

The command line used to run the altus denoiser.

Altus Only Files.

Save the file images for Altus but don't run the altus denoising.

Denoiser

The denoiser to use. If "None", no denoising. "Default" is an internal experimental denoiser.

Histogram bin count.

Histogram number of bins (default: 20).

Histogram patch distance threshold.

Histogram patch distance threshold (default: 1).

Histogram Gamma.

Histogram Gamma (default: 2.2).

Histogram maximum.

Histogram maximum (default: 2.5).

Radius of search windows.

Radius of search windows (default: 6).

Radius of patches.

Radius of patches (default: 1).

Random pixel order.

True for random pixel order (in case of grid artifacts) (default: False).

Spike removal prefiltering.

True for a spike removal prefiltering (default: False).

Spikes threshold factor.

Factor that is multiplied by standard deviation to get the threshold for classifying spikes during prefiltering. Put lower value to remove more spikes (default: 2).

Probability of skipping marked centers of denoised patches.

Probability of skipping marked centers of denoised patches. 1 accelerates a lot the computations. 0 helps removing potential grid artifacts (default: 1).

Number of scales for multi-scaling.

Number of scales for multi-scaling (default: 3).

Minimum eigen value for matrix inversion

Minimum eigen value for matrix inversion, in logarithmic form (i.e. 10^x)(default: -8).

log10

Denoiser

The denoiser to use. If "None", no denoising. "Default" is an internal experimental denoiser.

Batch

Force Render Split Layers

When enabled, force the rendering layers separately.

ForceSplitLayers

Generate Preview After

Generate a snapshot rendering after n minutes. Set this to 0 to disable the preview.

PreviewAfterPeriod

Stop After Preview

Stop after the preview snapshot is saved. Restarting rendering will resume from this checkpoint.

StopAfterPreview

Extended Max Samples

Maximum number of samples to reach after the first rendering stage is reached.

MaxSamplesPerPixel2

Extended Adaptive Threshold

Minumum adaptive threshold to reach after the first rendering stage is reached.

AdaptiveThreshold2

Checkpoint Period

Generate a checkpoint rendering every n minutes. If the rendering process was stopped, restarting will resume from this checkpoint. Set this to 0 to disable Checkpoints.

CheckpointPeriod

Checkpoint Location

The directory to store intermediate checkpoint data.

CheckpointLocation

Checkpoint Compression

The compression algorithm. Note tha pxr24 compresses much better but is slightly lossy.

CheckpointCompression

Performances

Bucket Size X

Width of a rendering bucket, in pixels. Decreasing this value can save some memory during the rendering, but will increase the render time.

Bucket Size Y

Height of a rendering bucket, in pixels. Decreasing this value can save some memory during the rendering, but will increase the render time.

Bucket Order

Changes bucket rendering order.

Adaptive Locality

if 1, a pixel must have as many sample as its neighbor, so no adaptive. 0.5 means at least half of its neighbor, more adaptive, but less continuity in the number of samples. 0 means no continuity at all.

Opacity Threshold

Amount of accumulated opacity to be considered fully opaque. Decreasing this value reduces memory consumption and rendering time for scenes with large number of semi-transparent objects, such as hair or volumes.

Max Opacity Depth

Maximum number of accumulated hits through a ray with opacity. This value controls the maximum number of semi-transparent layers the raytracer will accumulate. Above this count, the ray is considered culled. Increasing this value may resolve early depth culling at the cost of rendering time.

Ray Batch Size

Maximum number of rays to be shaded simultaneously.

Max Active Buckets

Controls the maximum number of active buckets per rendering thread in Bucket rendering mode. Increasing this value can improve performances when the buckets have few pixels that are hard to sample, especially in Progressive mode. Increasing this value also consumes more memory, especially when rendering deep images.

Thread Texture Count

Number of texture tiles held by rendering thread. This value controls how many texture tiles are kept in active memory by each thread. Higher values mean faster rendering, but higher memory usage. Note that actual texture memory is not duplicated across threads, but rather forced to stay resident in memory instead of being flushed.

Texture Diff Control

Controls the texture differentials interpretation. Legacy uses sharp texture lookups, while Parametric uses smoother texture lookups, with control from Texture Diff Max Anisotropy.

Texture Diff Aniso

Controls the texture differentials maximum ratio between ds and dt. Smaller values produce sharper textures, but require more memory, while higher produce blurrier textures but consume less memory.

Multithread Prim Load

Enables multithreaded load and subdivision of primitives. Check this option to reduce loading time. Note that this can aggressively increase the peak memory usage. Uncheck this to prevent large memory usage.

Default Surface Color

Surface color to use when a primitive has no surface shader nor suface color.

Offset Id

Offset the sample id.

Light Strategy

Strategy for direct lighting Sample the light, the bsdf, both or both with MIS weighting

DirectLightingMISStrategy

Use Default Settings

Force recommanded default settings

UseDefaultAdvanced

Max Vertices

Max vertices per path

MaxVertices

Max Diffuse Vertices

Max diffuse vertices per camerapath

MaxDiffuseVertices

Max Specular Vertices

Max specular vertices per path

MaxSpecularVertices

Max Refraction Vertices

Max refraction vertices per path

MaxRefractionVertices

Max Volume Vertices

Max volume vertices per path

MaxVolumeVertices

Light Diffuse

Default number of diffuse bounces.

LightDiffuseDepth

Light Volume

Default number of volume bounces.

LightVolumeDepth

Render Display Runtime Stats

Time interval to display threads rendering stats, in seconds.

Debug