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


Section Contents

Page Contents


V-Ray allows you to render to a V-Ray specific frame buffer, which has some additional capabilities:

  • Allows you to view all render elements in a single window and switch between them easily.
  • Keeps the image in full 32-bit floating-point format.
  • Allows you to choose the order in which the buckets are rendered.
  • Can store a list of recently rendered images and switch between them easily.


In addition, the V-Ray Frame Buffer contains the following dialogs:




UI Path: ||Interface Layout Tabs|| > V-Ray VFB



VFB Toolbars


Upper toolbar



This part of the toolbar sets the currently selected channel, as well as the preview mode. Choose which channels to see with the help of the buttons. You can also view the rendered image in monochromatic mode.
Saves the image into a single file. If a multi-channel type file is used (.exr, .vrimg) all the render elements will be saved in the same file.
Saves all the render elements into separate files.
Saves all image channels to a single file.
Opens an image file to be previewed in the V-Ray Frame Buffer.

Copies the current channel to the clipboard.

Clears the contents of the frame buffer. Sometimes helpful when starting a new render to prevent confusion with the previous image
Forces V-Ray to render the closest bucket found to the mouse pointer. Drag the mouse over the V-Ray frame buffer while rendering to see which buckers are rendered first. You can turn this on and of on-the-fly while rendering.
Allows you to render regions in the V-Ray VFB.
Links the V-Ray VFB to Pdplayer.
Stops the current rendering.
Repeat the last render.


Lower Toolbar


Opens the Color Corrections dialog which lets you define color corrections of various color channels. Right-click to dock or undock it.
Forces color clamping in the V-Ray VFB. Click and hold left mouse button to display the clamped colors in the V-Ray VFB.
Permanently opens the info dialog which will give you information about the pixel you right-click the mouse pointer on. If you right-click the mouse pointer over a pixel without turning this setting on you will see the info dialog only while your mouse button is down.
Enables the White balance color correction.
Enables the Hue/Saturation/Lightness color corrections.
Enables the color balance corrections.
Enables the levels color corrections.
Enables the curve color corrections.
Enables the exposure corrections.
Enables the usage of a background image.
Displays the image in sRGB color space. Click and hold the left mouse button to switch between sRGB color space and ICC.
Enables and disables the effect of the Look Up table loaded in the Color Corrections settings. Hold down to chose between LUT and OCIO color corrections.
Shows the V-Ray VFB history window. Right-click to dock or undock it.
Enables visualization the pixel aspect ratio.
Enables or disables stereoscopic preview. Click and hold down the left mouse button to pick between several stereoscopic modes.
Opens forth the Lens Effects  controls. Right-click to dock or undock them.

VFB History 

The V-Ray VFB allows the user to keep a history of previously rendered images. The images are stored as .vrimg files on a location specified by the user. In addition to keeping history this feature allows the user to set A and B image and compare them inside the VFB.

Enables the V-Ray VFB history.
Saves the current image from the VFB to the render history.
Loads the image selected in the Render history to the VFB.
Removes the selected image from the render history.
Enables or disables the comparison of images A and B from the VFB history. Click and hold down the left mouse button to change between horizontal and vertical comparison.
Sets the currently selected image as image A for A/B comparison in the VFB.
Sets the currently selected image as image B for A/B comparison in the VFB.
Swaps the A and B images.
Opens out the VFB history options which allow the user to specify the location where the history will be saved and the amount of disk space available. It also allows you to turn on auto-saving of each rendered image to the history.

The keyboard keys from 1 to 9 can be used to quickly switch between the first 9 images from the history.

Right-clicking on an image in the VFB history brings up a pop-up menu with some useful options:



Edit comment – Adds a text comment to the image; the comment appears in the "Details" column.

Set A – Sets the image as the 'A' image when comparing two images.

Set B – Sets the image as the 'B' image when comparing two images.

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

Delete – Deletes the selected image from the history.

Load V-Ray Settings – Applies the V-Ray Render settings stored in the stored image. 

Compare V-Ray Settings – Opens a comparison window that displays any differences in the current render setting with the saved ones.

Load Color Corrections – Loads the Color corrections saved in the stored image.

Reload History – Updates the Render History with the current .vrimgs in the VFB history folder.


Render History Settings

This window allows the user to specify VFB History settings such as to what location the history will be saved, and the amount of disk space to use.


History Directory – Specifies the location where render history images will be saved as V-Ray Image files (.vrimg).

Maximum Size on Disk (MB) – Specifies the max amount of disk space to use for the render history images. When the history exceeds the specified amount, the oldest images will be deleted.

Use Project Path – When enabled, creates a new vfb_history folder to use as the History Directory within the current Maya project directory.

Auto Save – When enabled, all rendered image will automatically be saved to the history.

Completed Renders Only – When enabled, only completed rendered images will automatically be saved to the history.

Auto Load Color Corrections – When enabled, color corrections saved in the stored image will automatically be loaded into the Color Corrections panel.

Clear – Clears all images in the render history.


VFB Shortcuts 

Here is the list of shortcuts you can use to navigate through the VFB image. Please note that VFB window must have the current focus for the shortcuts to have effect:


CTRL+Left click, CTRL+Right clickZoom in/Zoom out
Mouse wheelZoom in/Zoom out
Double-click left buttonZoom to 100%
Right click
Show the info dialog with the properties of the last pixel clicked. In order to see the info non-stop - turn on the info dialog button 
Page Up/Page DownSwitch between render elements
Middle button draggingPan (hand tool)
+ / -Zoom in/Zoom out
*Zoom to 100%
Arrow keysPan left, up, right, down
1-9Load the respective image from the VFB history
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.



  • Currently, saving JPEG, PNG, or OpenEXR images from the VFB will not respect the Modo Quality and Compression preferences specified under System > Preferences > File I/O > Image I/O. To save using the Modo preferences, use the Final Color Output item in the Shader Tree or the Choose Output Image option in the V-Ray > Render with V-Ray... windows (e.g. Render with V-Ray or Render with V-Ray Standalone).