Workflows

Clean Plate

Remove something from a shot by projecting a clean frame through your solved camera.

Clean Plate paints out things you don't want, using a different frame of the same shot as the source. Since the camera is already solved and you've given it geometry to work with, the reference frame gets projected into the exact perspective of the frame you're fixing. That's what stops the clone from sliding around.

Clean Plate isn't a node. It lives in the Image Editor sidebar under the Dope Track tab, because that's where you'll be painting.

Before You Start

You'll need:

• A solved camera in the scene, from Auto Track into Output 3D
• Rough geometry matching whatever you're painting over. A plane is often enough for a wall or a floor.
• A frame somewhere in the shot where the area you're fixing is clear

Paint On The Undistorted Plate

If your solve worked out the lens, paint on an undistorted plate rather than the original.

The projection is a straight pinhole projection through the solved camera. It doesn't bend anything, so it draws the reference frame as if the lens were perfect. Your original plate isn't, and the two won't line up. You see it worst near the edges, where a line that should sit along a curve in the plate runs straight across it instead.

Calibrate Lens on Auto Track is on by default, so most solves have distortion in them. If you left it on, this applies to you.

The fix is to work in the same undistorted space the projection is already using:

1. Run the plate through Lens Distortion in Undistort mode, fed from the same Auto Track that solved the shot.
2. Press Import as Footage on that node to get a clip of the straightened frames.
3. Point Clean Plate at that clip instead of the original.
4. Paint and save as normal.

If you need the finished plate back in original camera space, run it through a second Lens Distortion in Distort mode afterwards. Keep the overscan consistent between the two, since undistorting grows the frame and bending it back shrinks it again.

Footage with no lens distortion solved, or a shot from a lens flat enough not to matter, can be painted directly.

Setting It Up

Open an Image Editor, press N, pick the Dope Track tab.

1. Footage: the clip you're cleaning. Undistorted, if your solve calibrated the lens.
2. Dirty Frame: the frame you want to fix.
3. Ref Frame: a frame where that area is clean.
4. Camera: your solved camera. Leave it empty to use the scene camera.
5. Geometry: the mesh to project onto.
6. Output: where finished plates get saved.

ST Map Scale controls how detailed the projection is. Keep it low while you work, then raise it before the final save.

Painting

Press Open Clean Plate. The Image Editor turns into your paint surface.

Two ways to check your work as you go. Onion blends the reference over the dirty frame at whatever opacity you set. Wipe splits the view, and you choose where the split sits and which way it runs.

When the frame looks right, press Save Final Plate. This replays all your strokes at full projection quality, so it takes longer than the painting did.

Working Across Frames

Change the Dirty Frame and your current strokes get saved automatically first. The panel keeps a list of every frame you've painted, so you can work through a shot without losing anything.

Strokes stick around if you close the editor and come back later. They're saved with the scene, not just held in memory.

If The Clone Comes Out Black

The projection only produces pixels where a ray from the dirty frame's camera hits your geometry and lands somewhere inside the reference frame. Black usually means one of three things:

• Your geometry doesn't cover that part of the frame
• The camera solve isn't accurate in that area
• The reference frame never saw that spot

Extending the geometry fixes it most of the time.