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Tracking part 2 in Nuke

Tracking part 2 

 

Lens distortion Grid in Nuke

 

 I have an over 700 frames of a footage to track.

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1. Set up the project settings correctly. Press “s” to bring up the settings. Then change the format to the full resolution of the image. The resolution settings should be there at the bottom of the list.

Set your frame range. In this case, the frame range is “0 to 791″.

2. Connect to the Lens distortion which we made earlier. “Toggle Off and On” on the Lens distortion  node. Then you will see the difference between the settings. You should find that it correctly fixes the lens distortion. ( Tip: whenever you change the zoom or your focus, you have to re-shoot the lens distortion grid in theory.)

 “Command+x” to disconnect  the lens distortion  node from the footage for now.

Screen Shot 2013-11-14 at 2.32.33 PM

3. Get the “CameraTracker” and connect it directly to the source footage.

Screen Shot 2013-11-14 at 2.42.52 PM

4. We are going to copy the value of the distortion to the CameraTracker from the LensDistortion. Double click the lens distortion node, you will see the Radial Distortion 1 and the Radial Distortion 2.

In the CameraTracker property click “Lens” tap. As a default, you see Lens Distortion is set to “No Lens Distortion“. We are going to choose “Known Lens” ( In this case, we know our lens’s value).

For the Lens Type, choose “Spherical“.

5. Go to the LensDistortion property, Radial Distortion 1. Move your mouse to the animation menu box to the right,. Your mouse cursor will change to a mickey mouse hand. Grab it and move to the CameraTracker’s property’s Radial Distortion 1. Repeat the process for Radial Distortion 2.

lens_pro

Now you have the match values for the CameraTracker.

Screen Shot 2013-11-14 at 3.54.07 PM

Once you are done, check on “Undistort Input” on the CameraTrackers property. (Only in Nuke) or you could use the “Crop” node.

6. Now if you look through the image of the CameraTracker node and compare it to  the image of the LenDistortion node, the Understort Input selected for both, you should get the same images.

Tracking in Nuke

 

CameraTracker

7. For the CameraTracking relays the points have to be glued to the set. For instance: A person walking around in the set would be confused because of the CameraTracking. The movement should be closer to the camera. In this shot we have everything glued to the set.

Next thing we want to do is to go to tracking. Tap on the CameraTracker property and click on “Preview Features“. It is now making the scene trackable.

Crank up the value of the “Number of Feature” to 450.

(Tip: It is hard if the image is darker so we could use the Lookup node. Make sure to boost up the darker part of the image if it needs.)

For the “Feature Separation“, start with a value of 8. This is how far it is going to force the feature to be apart. We are going to reduce it more along the tracking.

Screen Shot 2013-11-14 at 4.30.12 PM

8. Go to the “Solver” tap. In this case we know the focal length.

Set the focal Length type to the “Known“. Focal Length to 17 ( In this case).

The film Back Size, x:15.81, y:8.88 ( In this case)

Screen Shot 2013-11-14 at 4.31.30 PM

9. How to run the track?

Go back to the main tap, CameraTracker, then click the “Track Features“.