Also known as the VFB, this UI window allows you to view your V-Ray renders as well as adding several important and convenient functions to display your renders.


Section Contents

Page Contents



The V-Ray Frame Buffer (VFB) is a V-Ray specific frame buffer with additional capabilities including render history and lens effects.

The VFB has many advantages:

  • 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 perform simple color corrections on the rendered image  
  • 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  
  • Allows you to apply lens effects to the rendered image
  • Allows you to switch between render channels via a dropdown of all pre-selected channels



VFB Toolbars

Top window tools

This dropdown gives access to render elements rendered for the scene. 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 scene will also appear in the drop-down.

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.

 The RGB Button switches the current channel to RGB color by default. When effects are applied, such as the VRayDenoiser or Lens Effects, the button will toggle between the effectsResult channel and RGB color channel.

Saves the current image (or the currently selected render element) into a single file.

Saves all the render elements into separate files. (available from flyout).

Saves all the render elements in a single file. If a multi-channel type file is used (.exr, .vrimg) all the render elements will be saved in the same file. (available from flyout).

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

This button copies the current channel to the clipboard along with the color corrections applied and the background image.

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 buckets are rendered first. You can turn this on and off 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.

Bottom window tools

Opens the Color Corrections dialogue 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 dialogue 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 color 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.

Opens the V-Ray Progress Window.

Stamp Tools



Toggles open Stamp Tools at the bottom of the VFB.

Applies a stamp with rendering metadata to the image.

Opens the Stamp Variables window to make it easy to copy different types of information onto the stamp.

Align stamp options; Click and hold to change from Left alignment to Right alignment or Center alignment.

Change stamp placement from align Bottom to align Top.

Choose Font window to change font, its style and size.

Stamp Variables

Stamp variables can be typed directly into the stamp textbox with a % symbol before and separated with a | symbol. Example: %rendertime | %frame | %camera

Also, use the Stamp variable window to select/highlight variables and clip on the Copy to stamp button to add them to the stamp textbox



vraycoreVersion of the V-Ray core
rendertimeThe render time for the last completed frame
vrayversionInternal V-Ray version
filenameMax project file name
primitivesNumber of internal V-Ray primitives used in rendering
computernameThe name of the computer this frame was rendered on
dateDate at the end of rendering
timeTime at the end of rendering
ramPhysical memory available (RAM)
vmemVirtual memory available
mhzThe speed in Mhz of the CPUs
cpuCPU type and number of CPUs available
osOS version
cameraCamera name (camera views only)
numPassesSampling level reached: number of passes
numSubdivsSampling level reached: number of subdivs


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. This history can be accessed through the H icon at the bottom of the VFB window. The Render history can be docked to the VFB (as shown below) or can float separately. In addition to keeping history, this feature can display two images in the VFB for comparison (as shown below), which is revealed via a sliding division line. History files are stored as .vrimg files in a user-specified folder. 



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.


Swaps the A and B images.
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.

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.
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 – Allows you to add 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.


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:

Mouse Description
CTRL+Left click,
CTRL+Right click
Zoom in/Zoom out
Mouse wheelZoom in/Zoom out
Double-click left buttonZoom to 100%
Right click
Show the info dialogue with the properties of the last pixel clicked. In order to see the info non-stop - turn on the info dialogue 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.


Changing the background color

You can change the background color of the VFB by right-clicking on the background and selecting one of the options from the pop-up menu.