Table of Contents

This page provides information on the New V-Ray Frame Buffer and its features.



The New V-Ray Frame Buffer (VFB) is a second-generation V-Ray virtual frame buffer.

The New VFB is much more than a render image holder window, with Light Mix capabilities for modifying the project lighting after rendering and Layer Compositing for a higher level of post-processing adjustments.

  • Image preview:
    Loads render elements channels via a dropdown list;
    Works with display corrections;
    Loads various 8bit and 32bit file formats, including V-Ray resumable files;
    Image comparison between 2 or 4 renders;
  • Image management:
    Keeps the rendered image in full 32-bit floating-point format;
    Stores history of rendered images with their post rendering corrections;
    Saves corrected output to various image formats;
  • Image editing and post-processing:
    Add Color Corrections to rendered image and its elements;
    Layer Compositing for anything from a simple Back to Beauty workflow or advanced compositing;
    LightMix adjustment of the project lighting after rendering the image;
  • Project editing:
    Modifies actual lights values by transferring updated intensity and color from LightMix mode;
  • Render management:
    Denoiser control;
    Region rendering control and test resolution;
    Allows you to choose the order in which the buckets are rendered.
  • Collaboration:
    Shares images with other Chaos users in Chaos Cloud Collaboration.

VFB Cloud Collaboration is a new feature available only in V-Ray 6 for Revit.

To learn how to work with the New VFB, check the Courseware section.



UI Path


||Revit Ribbon|| > V-Ray tab > Render panel > Show / Hide Frame Buffer



VFB Menu

The V-Ray Frame Buffer menu holds the main frame buffer commands. Some of the options are also available in the VFB toolbar for quick access.


Menu Options



Save current channel – Saves the currently loaded channel to an image file format.

Save all image channels to separate files – Saves all the render elements to separate files. Press the options() button to open a menu with more settings.

Save all image channels to single file – Saves the image to a single multi-channel EXR or .vrimg file.

Load image – Opens an image file to be previewed in the V-Ray Frame Buffer.

Batch image processing - Allows processing of multiple .vrimg files with the same layer tree changes at the same time.

Upload image to Chaos Collaboration – Uploads your rendered images to Chaos Cloud Collaboration where other users can add comments and annotations.

Save all image channels to separate files options

Save VFB color corrections to render elements – When enabled, all color corrections are saved to the render channels (as opposed to only the RGB and effectsResult channels).

Batch Image Processing

Input folder – Specifies a path to start images.

Output folder – Specifies a path for the output images.

Layer preset – Specifies a layer tree corrections preset.

Output filenames suffix – Specifies a suffix added to the output image filenames.

Overwrite existing – Enables overwrite of existing files with the same name in the output folder.


Abort rendering – Stops the current rendering.

Render – Starts Production Rendering.


Follow mouse – Renders the closest bucket found to the mouse pointer, when using the bucket image sampler. If the progressive sampler is used, V-Ray samples the closest pixels to the mouse pointer.

Follow mouse – Drag the mouse over the VFB while rendering to change what part of the image is sampled first;
Follow mouse (locked) – Locks the bucket (or sampling) starting point.

Copy current channel to clipboard – Copies the current channel to the clipboard.

Clear image – Clears the contents of the frame buffer. This is useful when starting a new render to prevent confusion with the previous image.


Display color space –Specifies the color space, in which the image is displayed.

None – Does not specify a color space;
sRGB – Displays the image in sRGB color space;
OCIO – Displays the image in a color space loaded from an OCIO configuration file;
ICC – Displays the image in a color space loaded from an ICC configuration file;
Gamma 2.2 – Displays the image in Gamma 2.2 color space.

Zoom VFB – Zooms in/out the rendered image in the VFB.

Zoom 50% – Zooms out to 50%;
Zoom 100% – Zooms to 100%. Alternatively, double-click in the VFB with the left mouse button;
Zoom 150% – Zooms in to 150%.
Zoom to fit (F)Zooms the current image to fit in the VFB. If Render Region is active – zooms to the region.

Channels – Chooses which channels to see.

View red channel – Displays the red channel;
View green channel – Displays the green channel;
View blue channel – Displays the blue channel;
Switch to alpha channel – Displays the alpha channel;
Monochromatic mode –Displays the image in monochromatic mode.

Test resolutionEnables test resolution in VFB. The submenu allows choosing a percentage of the render resolution to set as the test resolution. You can choose between 10%, 25%, 50%, 75%, 110%, 125% and 150%. Note: This only affects V-Ray and does not affect the native 3ds Max test resolution setting found under 3ds Max's Render Setup dialog.

Color clamping – Opens the color clamping submenu options:

Force color clamping – Forces color clamping;
View clamped colors – Displays the clamped colors.

Use pixel aspect – Enables visualization of the pixel aspect ratio.

Flip – Mirrors the image in the VFB. This is a view only option, the flipped image cannot be exported. This function is only active while holding the menu button or the hotkey for the corresponding type of flip. The effect does not interrupt interactive rendering.

Flip horizontally – Mirrors the image horizontally.

Flip vertically – Mirrors the image vertically.

Panorama View – Shows the image in 360° view. Hold the middle mouse button and move the mouse to look around. The field of view can be altered by scrolling.

Show History – Shows the History panel.

Show Layers – Shows the Layers panel.


VFB settings – Opens the VFB Settings window with setting adjustment options for Render View, Render Region, History, and Layers.

VFB Toolbar

This dropdown gives access to render elements rendered for the project. The selected render element is displayed in the VFB. By default, the RGB color and Alpha render elements are available. Any additional render elements that have been added to the project also appear in the drop-down.

Displays the coordinates of the mouse pointer.

Specifies the sampled area size. Select the arrow to open a context menu with the available sampled area sizes: 1x1, 3x3, 5x5, and 7x7.

Specifies whether color and display corrections are applied (RGB) or not (Raw) when showing the sampled pixel values at the current mouse pointer position.

Displays the RGB pixel values at the current mouse pointer position before applying any color corrections.

Specifies RGB values. Select the arrow to open a context menu with the available option.

None – Does not specify the RGB value.
HSV – Specifies the Hue, Saturation, and Value of the pixel under the current mouse position.
Web – Specifies the HEX of the pixel under the current mouse position.
8bit – Specifies the 8bit color palette of the pixel under the current mouse position.

Displays the Hue, Saturation, and Value of the pixel under the current mouse position when HSV is selected.

Displays the HEX of the pixel under the current mouse position when Web is selected.

Displays the 8bit color palette of the pixel under the current mouse position when 8bit is selected.

Locks the mouse pointer coordinates and displays information for the selected pixel.

Shows corrected colors.

Shows the V-Ray log.

Displays the red channel.

Displays the green channel.

Displays the blue channel.

Displays the Alpha channel.

Saves the image to disk. Press and hold the icon to bring up the submenu:

Save current channel – Saves the current channel to an image file format;

Save all image channels to separate files – Saves all the render elements into separate files; Use  to save the VFB color corrections to render elements.

Save all image channels to single file – Saves the image into a single multi-channel EXR or .vrimg file.

Upload image to Chaos Collaboration – Opens the Chaos Cloud Collaboration panel.

Clears the contents of the frame buffer. This is useful when starting a new render to prevent confusion with the previous image.

Renders the closest bucket found to the mouse pointer, when using the bucket image sampler. If the progressive sampler is used, V-Ray samples the closest pixels to the mouse pointer. With this option enabled, right-click on the image and select Lock bucket starting point to lock the bucket (or sampling) starting point.

Allows you to render regions in the VFB. See the Render Region section for more information.

Stops the current rendering.

Starts Production Rendering.

Render History

The V-Ray VFB keeps a history of previously rendered images, and lists each with a number, thumbnail, and textual details in the Render history panel. Call up to four images from the history to be compared in the VFB (as shown below). History files are stored as .vrimg files in a user-specified folder. Configure the render history settings in the VFB Settings window.






Saves the current image from the VFB to the render history. The image is placed at the top of the render history list.

Enables or disables image A/B vertical comparison. Select images A and B from the render history.

Enables or disables image A/B horizontal comparison. Select images A and B from the render history.

Enables or disables image A/B/C/D comparison. Select images A, B, C, and D from the render history.

Loads the selected image from the render history to the VFB.

Removes the selected image from the render history.

Search field for filtering images based on the project's paths and notes.

Use the keyboard keys from 1 to 9 to quickly load the first 9 images from the history to the VFB.

Edit note – Add a text comment to the image. The comment appears below the image.

Set A – Sets the render as A image for A/B comparison.

Set B –  Sets the render as B image for A/B comparison.

Load to VFB – Loads the selected image in the VFB (same as double-clicking on the image).

Delete – Deletes the selected image from history. The image is moved to the system's Recycle Bin with the option to be restored from there if needed.

Load layers – Loads the layer tree preset of the selected image.

Load V-Ray settings – Loads the V-Ray settings used for the  saved render.

Compare V-Ray settings – Compare the render settings of saved renders in the Compare V-Ray settings dialogue.

Image Info – Opens a window containing detailed information about the image, including, but not limited to Camera, Aperture, FOV, Target Distance, V-Ray version, render time. Have in mind that the camera values are saved in system units. Also, the vrayrevison info displayed in the list is not related to the saved .vrimg file but to the current V-Ray build installed for Revit.

Open scene – Opens the rendered project in the viewport. This option works as long as the initial file path of the project has not changed after the render.

Copy scene path – Copies the full path to the project.

Copy project path – Copies the full path to the project.

Upload image(s) to Chaos Collaboration – Opens the Chaos Cloud Collaboration panel where you can share your images with others and receive comments and annotations.  

Reload history – Re-reads the history image list. This may be needed if the history folder is updated outside of 3ds Max (e.g. from another Revit session).

Manually saved .vrimg files can also be added to the History folder, but they need to be saved with all image channels in one .vrimg file to keep the complete image info.



The New V-Ray Frame Buffer includes a suite of color corrections and tools for adjusting the image. The tools are added as layers and displayed in a layer tree. Enable or disable a particular tool using the visibility icon () to the left of its name. The icon indicates that a layer is disabled.

For more information on using the Layers, see the Layers page.






Creates a layer. Multiple layers of the same type can be added.

Folder – Allows grouping multiple layers;
Background – Adds a background color correction layer;
Render Element – Selects a render element from your image that you can use in compositing. This is only available when the Source layer is set to Composite;
Constant – Adds a solid color that can be used to achieve an effect on another layer (for example to multiply by the constant);
Exposure – Adds an Exposure color correction layer;
White Balance – Adds a White Balance color correction layer;
Hue/Saturation – Adds a Hue/Saturation color correction layer;
Color Balance – Adds a Color Balance color correction layer;
Curves – Adds a Curves color correction layer;
Lookup Table – A Lookup Table layer allows loading a LUT file for color transformations;
Filmic Tonemap – Contains different types of mapping curves and gamma corrections. Also allows selection of a color space.
Integer mask element – Mask is used with integer render elements like VRayRenderID, VRayObjectID, and VRayMtlID Render Elements.
MultiMatte mask element – Mask is based on the MultiMatte Render Element.
Proportion Guide
Adds a proportion guide layer.

For more information, see the Layers page.

Deletes the selected layer(s).

Saves a layer tree preset.

Loads a layer tree preset.

Quick access to custom layer presets. You must set the path to it in the VFB Settings.

Undo create layer.

Redo create layer.







ResetResets all changes done to the selected layer.
SaveSaves the layer as a preset.
LoadLoads a preset for the selected layer.
DeleteDeletes the selected layer.
Save as LUTBakes all the color corrections to a LUT file.
New LayerCreates a new layer.
DuplicateDuplicates the selected layer.
Blend ModesSpecifies how the selected layer blends with the result from all layers below it.




The Stats section provides track reports about the project, the engine, the devices, the performance, and the memory.

Memory tracking is always enabled and there is no need for configuration.

Right-click to display a context menu, allowing you to copy the Stats values.





The Log panel provides messages about the render process. Verbosity control is available and you can filter the type of messages shown in the Log: AllError OnlyError & Warnings, or Error, Warnings & info. Additional options are available when you click on the Open options  button:

Show progress – Shows a completion percent of each task (e.g. building Light Cache).

Wrap – Wraps longer lines in order to avoid horizontal scroll.

Undock – Docks/undocks the Log tab.

Note that the V-Ray Log is also accessible via the Show log button.

The Log tab can be detached and used as a separate window or docked elsewhere.

Ctr+F opens a search field at the bottom of the Log tab.




VFB Shortcuts

These shortcuts navigate through the VFB image. Please note that the VFB window must have the current focus for the shortcuts to have effect:


Mouse wheelZoom in/Zoom out
Double-click left buttonZoom to 100%
Middle button draggingPan (hand tool)
Ctrl+Shift+Left clickZoom in the rendered image
Ctrl+Shift+Right clickZoom out the rendered image
HShow/hide history
PShow/hide only layers tree
Ctrl+LShow/hide whole right panel
F11Toggle full screen
SShow/hide VFB settings
History/Render View
EEnable history A/B/C/D compare mode
QEnable history A/B horizontal compare mode
WEnable history A/B vertical compare mode
NEdit a note in VFB History panel
1-9Load the respective image from the new VFB history
Layers/Property Panel
Ctrl+YRedo various actions related to layers such as create, delete, reorder or modify a layer.
Ctrl+ZUndo various actions related to layers such as create, delete, reorder or modify a layer.
DelDelete layer
Message Log
EscClose search
Ctrl+FActivate the Search field in Log tab
ReturnFind next
Shift+ReturnFind previous
Render View
EscAbort render
Ctrl+CCopy the VFB image to the Windows clipboard; the image is copied exactly as it appears on the screen (meaning sRGB/LUT/OCIO etc. corrections are applied). The full resolution image is copied to the clipboard, even if the VFB view is zoomed in/out.
Ctrl+OLoad image
LLock the mouse pointer coordinates and display information for the selected pixel, i.e. activate the Lock pixel info coordinates button.
Arrow keysPan image left, up, right, down
ASwitch to Alpha channel
BView Blue channel
GView Green channel
RView Red channel
Page DownView next channel
Page UpView previous channel
*Zoom to 100%
+ / =Zoom in
-/_Zoom out
FFit region or whole image in the VFB


Render Region

Use Render Region in both Interactive and Production rendering modes to isolate only part of the frame for rendering.

When saving single-channel .exr files, the render region is ignored and a full frame is always saved. This applies when saving the .exr  through VFB.

Saving multi-channel .exr files writes just the render region data in the file by default but it has the option to save the full frame instead. In order to save the render region with the rest of the frame, set its exr data window option to Whole Image. Saving multi-channel .exr files from VFB > Save all channels to single file saves the render region when it is enabled from the VFB. This happens even if you have selected a render region on top of the already rendered frame, without an actual region used in the rendering process. To save the full frame from VFB, disable the render region.



  • The OpenEXR file format is an open file format for high dynamic range images originally developed by Industrial Light and Magic. The official site of the OpenEXR file format is
  • If Lens Effects or the Denoiser render element are enabled, then the RGB Color channel is saved with the name RGB_color and the effectsResult channel is saved as effectsResult when saving all channels from VFB.
  • If an 8-bit file is saved through the VFB or the Render Output / Save image settings, the color space (for example sRGB) is embedded and the image appears as in the frame buffer when loaded in an external image viewer. If a 32-bit (exr, hdr, tif) image is saved, it remains linear and relies on the external image viewer to handle the display color space.
  • Global Color Correction files (*.vccglb) from the old VFB cannot be loaded in the new V-Ray Frame Buffer.
  • .vrimg is a Chaos proprietary file format used by the V-Ray Frame Buffer to store the rendered image incrementally (bucket by bucket) while rendering in full floating-point format, with all available render elements. It is used as a render output but it is not recommended to use it as a texture file format. VRIMG contains metadata, i.e. render statistics. It supports dynamic bucket size.

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