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Depth Map and Surface Tracker – DaVinci Resolve 18 Tutorial

Resolve 18 is filled with some really interesting features that can take your edit to the next level. Watch the video or read on to learn how to effectively use the Surface Tracker and Depth Map effects in your workflow.

For this tutorial, we’ll be using this beautiful hiking shot below. You’ll learn how to use the Surface Tracker to remove the trail marker that’s painted on the rock, and the Depth Map effect to color grade the sky differently from the foreground in this image. Let’s start with removing the trail marker.

On the left, an image of mountains with an overlay showing the areas that the editor wants to color grade or remove in the clip. On the right, a visual guide of adding a Surface Tracker node and defining a boundary to use the node on in DaVinci Resolve
Find the Depth map in the Effects Library, feed input 1 and 2 the same image, and click the image to add the nodes

Surface Tracking

Open up your effects browser, find the Surface Tracker and drag it into the node tree. The Surface Tracker has two inputs – input one is for the image that you are tracking and attempting to patch. Input two is for the patch that you’re going to project onto the Surface Tracker. For the time being, feed input one and input two the same image, it’ll become clearer why we’re doing that later.

When you select the Surface Tracker node, the OpenFX overlay is automatically selected in your viewer. As shown in the image above, by clicking on the preview of the clip, you can create the boundary of the surface track. In this case, we’ve deliberately chosen to do this on the last frame of the clip,  because the camera’s pushing closer and you get the best view of the trail marker on the last frame of the clip.

A visual guide on adjusting the settings for the Surface Tracker node in DaVinci Resolve
Once you’ve adjusted the settings, track backwards or forwards through the shot, depending on what frame you used as a reference

Next, head over to the mesh tab. There’s two different ways for Resolve to generate this mesh: the first is automatic (1), the second is using a uniform grid. For this example, stick with automatic point locations, because there’s plenty of nice crisp features for Resolve to track. Now, go to the track tab, and change the quality from faster to better (2). And because we’re on the last frame of video, you’ll want to click track backwards (3).

Now, we can head to the results tab. The Surface Tracker is currently set to warping input two onto input one (4) – it’s basically taking a snapshot of that second input, just one single frame, and warping it onto that surface as the video plays out.

Which frame is it using? At the moment, it’s currently using the first frame, so switch the overlay source to our reference frame. Because you started the track from the last frame of the video, by default, that frame has been set as the reference frame (5). You can see here that reference frame is frame 452 (6). It’s pretty easy to change your reference frame, just position the playhead and click, set to current.

A visual demonstration of a DaVinci Resolve user removing a marker on the surface of a rock in a video clip
Drag the Reference Frame upwards to replace the marker with clean rock

At this point, you might be wondering why the trail marker is just as visible as ever. This is because we’re now going to reposition the overlay that is being applied to the Surface Tracker, to finally get the effect we want.

You can shift the overlay using sliders, or alternatively, just by clicking and dragging on the canvas (7). When you move the canvas around be careful, if you click and drag on the red lines, you will warp or distort the image. But if you click somewhere in the middle, it’ll just do a simple translation.

We’ve got a nice clean patch of rock under the trail marker, so move the overlay up to use the clean rock to patch the trail marker. Adjust the softness so you don’t get a hard edge on the Surface Tracker’s bounds (8). Finally, pipe the patch through a corrector node (9), and use a little bit of gamma to match the rocks better.

Depth Mapping

Next, let’s have a look at the Depth Map effect. Start by dragging the effect into your notary. At the moment, the Depth Map effect is a little bit processor intensive, so get ready to wait a while and to put up with slower playback.

As you can see by the preview next to the color wheels, it’s done a pretty good job of working out the depth in the scene. Because this is an OpenFX node, it’s not a corrector node, so you can’t apply any corrections to it.

What you need to do is send the alpha channel from this node to an ordinary corrector node, and then you can use it to make adjustments. If you head over to node five and turn on highlight mode, you’ll see that it is just selecting the foreground of the image – that’s easy for me to fix in the node key controls, you can just invert the key (1).

In DaVinci Resolve, an editor adds a Depth Map node and connects the alpha channel to a corrector node
Send the Alpha Channel of the Depth Map Node to a corrector node to make any adjustments

This isn’t particularly helpful at the moment – although it is selecting the sky, it’s also selecting a lot of the foreground. You’ll notice though that the foreground becomes more transparent the closer we get to the camera.

Let’s head back to the Depth Map node. Turn your preview back on (2), and check the box ‘adjust map levels’ (3). By manipulating the near limit and the far limit, you can make the Depth Map more aggressive.

It’s basically an alpha map – white represents parts of the image that are going to be opaque. Black represents parts of the image that are going to be transparent (with the caveat that you’ve flipped the key in your corrector node). Turn the Depth Map preview back off and go back to corrector node number five and drive some cyan and blue into the gamma (4).

In DaVinci Resolve, on the left a Depth Map node preview shows what part of the image the node will manipulate. On the right, an editor uses the Depth Map node to color grade the background of the footage
After adjusting the Depth Map, feed it into a corrector node, using a power gradient to change the background only

Next, grab another corrector node, connect to the alpha channels, and select a power gradient (5). Use this just to add a little bit of a gradient to the sky, so it gets darker as you go up (6). No matter how far down you drag this gradient window, the grade is not going to affect the foreground of the image because you’re using the Depth Map to control its opacity.

The Final Result

This completes our editing for this shot – you can see the clip before editing, and a preview of the new clip below. When playing back the footage we found you get about six to eight frames per second on an M1 Max MacBook Pro. Maybe this will get a little bit better with subsequent releases that make the effect more efficient, but for now this is more than good enough for you to preview the effects of the grade.

Two images of the same footage, showing before and after editing the clip with a Depth Map and Surface Tracker.

Improving the Surface Mesh

Here are some other clips that allow us to look at the Surface Tracker and Depth Map effect in different scenarios. The Surface Tracker does not use your original source media, it uses whatever changes that you’ve made in any of the corrector nodes that are upstream from it. That means there are things that you can do that make your image easier or harder to track.

To demonstrate, in the clip shown below, every time you click ‘Regenerate Mesh’, Resolve will analyze the image and create a mesh based on the points of interest it finds, such as the jacket.

Look what happens if you turn on the upstream node that improves the contrast and the visibility of the jacket. When you come back into the mesh tab and hit regenerate mesh, you’ll see that it identifies way more points as a part of its mesh.

Two screenshots of DaVinci Resolve, comparing how a corrector node can improve a Surface Tracker Node
Using corrector nodes can improve the quality of surface tracking

On flat images like the one below, the Depth Map effect is fantastic for isolating foreground subjects.

Try the isolation tools – in this case the subject is in the foreground, so you would decrease the target depth (1). The plugin won’t give you a pixel perfect mask, so it’s not a substitute for properly rotoscoping someone out. But if you head back to the Depth Map, you can turn on the map finesse post processing controls and add a little bit of blur (2). You can now manipulate just the foreground of this image.

A demonstration of how adjusting the settings of a Depth Map node in DaVinci Resolve can be used to isolate subjects in the foreground of a clip
Change the Target Depth and add a little blur to isolate foreground subjects in a flat image

Combining Nodes

Depth Map does a really good job even with complex scenes like the one below. In Depth Map, you can see the model walking, all of the sign posts, the and the bus that’s passing. These adjust map levels controls are really, really good, but there are other ways that you can manipulate the Depth Map.

For example, if you pipe its output to an ordinary corrector node, you can then manipulate that Depth Map using curves. There are scenarios where you might find that a more intuitive way of editing it.

A visual guide for DaVinci Resolve, showing how a corrector node can be used in combination with a Depth Map to manipulate the area the Depth Map node selects
Use a Corrector Node to manipulate the Depth Map itself with the Curves Tool

Wrap Up

When utilized correctly, Depth Mapping and Surface Tracking are powerful tools that can make color grading and other post-processing effects a lot easier!

If you’re interested in getting started with Resolve, check out our DaVinci Resolve Quickstart course. For more tutorials about creative editing in general be sure to visit our training page.

There, you can download free editing guides along with high quality video courses created by our team of professional Hollywood editors.





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