​

These settings will help you monitor, troubleshoot and optimize your Arnold renders.

Log

Arnold can generate a log reporting all the steps needed to render an image and any warnings and errors encountered by the renderer. This log also provides detailed statistics that are useful for debugging, optimizing, and benchmarking renders.

_{Write Log file also found under File->Preferences, Rendering Tab, Messages group.}

Log Console

Shows the log in the render message window.

Log File

Enables the output log file.

Verbosity Level

Specifies the amount of information in the render message window (needs the 'Show' flags or in the output log file.

Detailed Texture Statistics

Enable very useful per texture statistics, with time spent on texture queries, amount of texture data read, memory consumption, etc.

Max Warnings

Limits the number of warning messages (of a similar type) that are sent to the log.

Statistics

An extensive set of tools that allow you to easily identify performance issues and optimize renders. Additional timing statistics organized by both nodes and categories can be output to HTML-based visual reports or a JSON files. This makes it possible to know which objects are most expensive to render and which parts of the renderer took the most amount of time.

HTML Report

The Arnold Render Report is a visualization tool for reviewing charts and statistics such as frame time, memory usage, and texture stats for a rendered image. Enable HTML Report to generate an HTML file that includes all the render statistics.

View

Opens the Render Report in a web browser.

JSON Stats

Creates a json file with the render statistics and information that you can see in an Arnold log. If you use append mode, you get a file with the separate statistics for each render (for example, each frame in a sequence, or each pass in an IPR render).

Profile

Saves detailed profiling visualizations by outputting trace information into a file, such as "my_profile.json". You can then load the file into the Google Chrome web browser using https://ui.perfetto.dev/ or into https://www.speedscope.app/.

Profile File Path

The path of the file where the profile will be written.

Error Handling

Abort on Error

If set, rendering will stop as soon as an error is detected. This is the recommended setting. In general, you should not ignore important error messages, or you'll risk crashes, rendering artifacts, and undefined behavior.

Texture Error Color

Color used to report texture errors.

NaN Error Color

Color used to report NaN's.

Feature Overrides

This group of switches allows you to disable a number of important rendering features.

User Options

This is a general-purpose property, consisting of a string. This string field can be set to override any parameter of an Arnold core node. This allows you to, for example, access and set Arnold core parameters currently not exposed in the user interface. The property can be applied to poly-meshes, hair, and lights.

For example, if sharper renders are important, you could set texture_max_sharpen to 1.5.

You can query the list of parameters an Arnold core node has by using a kick. For instance, you can get the attribute names of a polymesh node by using:

kick -info polymesh

Always refer to the core Arnold nodes (see the bottom of page), and not to the parameter's name as exposed in the Arnold plugin.

If you want to set multiple Arnold parameters in a user_options string, you can use any whitespace (spaces, tabs, newlines e.g., \n) that you would use in an actual ASS file.

_{'kick -info polymesh' parameters available through kick}

Distant lights support the normalize attribute, so you can disable normalize (before it was always enabled and the normalize attribute was ignored). You can use the Arnold option usd_legacy_distant_light_normalize to roll back to the previous behaviour.