This page provides information about the Frame buffer settings tab in the Render settings window. 


The options available in this tab will allow you to set additional behavior for the Corona VFB, including the Image filter.

UI Path: ||Render settings window|| > Corona > Frame buffer settings tab



Frame buffer

Clear VFB in between renders – When enabled, the frame buffer is reset to black before each rendering. When disabled, the last render stays on and is gradually replaced by the new one.

Render stamp – When enabled, text with render information overlays on the bottom right corner of the rendered output. You can click the little > button before the checkbox to see the list of all available %-variables you can use.

The content of the render stamp accepts text and the special %-variables listed under the > button.

Renderstamp varialbleExplanation
%ptpPerformance: Parsing time (in milliseconds)
%ptgPerformance: Geometry preprocessing time (in milliseconds)
%ptsPerformance: Secondary solver precomputation time (in milliseconds)
%ptdPerformance: Denoising time (in milliseconds)
%ptPerformance: Total elapsed time
%prPerformance: Rays per second
%psPerformance: Rays per sample
%ppPerformance: Passes
%pePerformance: Noise level
%slScene: Number of light primitives
%soScene: Number of objects
%siScene: Number of instanced primitives
%suScene: Number of unique primitives
%sdScene: Number of displacement primitives
%cCPU name
%ctNumber of CPU thread(s)
%bnCorona build name
%bCorona build datestamp
%dCurrent date/time
%hCurrent time
%fCurrently rendered filename
%nActual frame number
%oOutput filename
%vCurrent camera name
%iThis computer name
%mcMemory currently used by Corona
%mcpPeak memory used by Corona
%mpVirtual memory currently used by the host application + Corona Renderer
%mppPeak virtual memory used by the host application + Corona Renderer for that session of the host application
%msVirtual memory used by the system

Image filter

Type – The image pre-filters suppress Moiré patterns and other artifacts by slightly blurring the image. Most filters produce visually almost equal results.

Available filter types are:

High Quality – This filter produces better anti-aliasing and DoF than other filters. It does not work with AI denoising.
Box – This filter has the most significant blurring of all the filters.
Tent – This filter offers a good tradeoff between blurring and sharpness.
Symmetric tent – This filter is a variant of the tent filter with bigger diagonal blurring.
Parabolic – This filter has the second most significant blurring of the filters.
Hann – This filter has low diagonal blurring and a smaller tail than the other filters.
Blackman-Harris – This filter is the sharpest, resulting in the least blurring of all the filters (except for None).
None – This option disables the filtering entirely, resulting in a perfectly sharp image.

Width [px] – The filter radius in pixels. A larger value slightly blurs the image to improve anti-aliasing and removes the Moiré effect. The default value of 2.0 works fine in most cases.

Highlight clamping – Clamps all samples to this maximum value before they are written into the frame buffer. This can help to reduce noise and improve anti-aliasing around bright light edges at the cost of bias. Setting the value too low results in visibly clamped highlights. Set to 0 to disable for unbiased, highest-quality output.



Other Render settings tabs