Lens breathing compensation

Lens breathing refers to a shifting of the angle of view or focal length of a lens when the focus changes. Catalyst Prepare allows you to use metadata from clips to compensate for the effect of lens breathing.

  1. Click the Organize button at the top of the Catalyst Prepare window to view the Media Browser.

  2. Select the clip you want to correct. An on a thumbnail indicates a clip that contains metadata for lens breathing compensation.

    The lens breathing icon is not displayed for clips on FTP devices, XDCAM Station volumes via CIFS, XDCAM decks, XDCAM Drive units, or Optical Disc Archive volumes.

    For information about camera settings for enabling compensation using metadata, please see Information on Software Applications.

    Lens breathing compensation is not supported when changing camera settings or detaching the lens during clip recording.

  3. Perform any of the following actions to display the Correct clip workspace:

    • Click the Lens breathing button at the bottom of the Catalyst Prepare window.

    • Right-click the clip in the Organize pane and choose Lens breathing compensation from the shortcut menu.

    The Lens breathing button is not available when multiple clips are selected.

    When the Catalyst Prepare window is resized, the Adjust color , Lens breathing compensation , and Stabilize clip buttons are available in the Adjustments menu .

  4. Use the Correct clip workspace to preview and adjust settings for the selected clip:

    1. Set the Mark In/Out points to indicate the portion of the clip you want to correct. For more information, see "Marking in and out points for playback."

    2. Choose a Compensation mode setting to compensate for lens breathing:

      • Select the Auto button in the Inspector to adjust cropping automatically.

        Item

        Description

        Minimum cropping ratio

        Drag the slider to set the amount of cropping that can be applied to compensate for lens breathing.

        This setting is persisted when changing the selected clip or exiting the Correct clip workspace.

        When correcting a clip using a Minimum crop resolution setting that is too large, clips with significant lens breathing may exhibit a black border around the frame. We recommend using a setting that is close to the default cropping ratio value in manual mode. To check the default manual cropping ratio, click the Manual button and double-click the Cropping ratio slider handle to reset the setting to its default.

        Corrected crop resolution

        Displays the dimensions of the frame after cropping is applied.

        Minimum crop resolution

        Displays the minimum dimensions of the frame based on the Minimum cropping ratio setting.

      • Select the Manual button if you want to adjust compensation settings.

        Item

        Description

        Cropping ratio

        Drag the slider to set the maximum amount of cropping that is applied to compensate for lens breathing.

        This setting is persisted when changing the selected clip.

        When correcting a clip using a Cropping ratio setting larger than the default value, clips with significant lens breathing may exhibit a black border around the frame. We recommend using a Cropping ratio setting that is close to the default value. You can double-click the slider handle to reset the setting to its default.

        Corrected crop resolution

        Displays the dimensions of the frame after cropping is applied.

      • Select the Off button if you do not want Catalyst Prepare to compensate for lens breathing. If the clip includes in-camera breathing compensation, it will be preserved.

  5. Click the Analyze button to analyze the selected clip and update the preview to show the corrected clip.

    After analysis, the Output summary section of the Info panel displays the corrected crop resolution.

    If you change the selected clip, the preview will indicate that the clip has not been analyzed. Click the Analyze button at the bottom of the workspace to analyze the selected clip and update the preview to show the corrected clip.

  6. Click the Before/After button at the top of the video preview to choose a preview mode so you can compare your original and corrected video before applying the changes, and then use the transport controls below the timeline to preview the clip.

    • Before: the clip is displayed in its original state.

    • After: the cropped and corrected clip is displayed.

    • 2 Up: two full frames are displayed in a split-screen view with the original video on the left and the corrected video on the right.

    In some cases, Catalyst lens breathing compensation can be less effective than in-camera lens breathing compensation if stabilization is also enabled. Use the Preview pane to compare the original and corrected clip. You can set Stabilization mode or Compensation mode to Off as needed before exporting the corrected clip.

  7. To save a clip with the corrected settings, click the Export button at the top of the Catalyst Prepare window, and use the Export pane to choose a destination and format for your exported files. Click the Export button at the bottom of the Export pane to start exporting the selected clip.

    If multiple clips are selected, the Export button at the bottom of the Export pane is displayed as Batch Export. Click to display a confirmation dialog that lists all selected clips. You can select or clear check boxes to add or remove clips from the selection. Click OK to begin exporting the selected clips using the current settings.

    For more information about the controls, please see "Exporting media from a library".