Motion Tracking & Object Tracking inside Cinema 4D: Can we track without using a Survey Shot?

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Can we track without using a Survey Shot?

With the help of the Focal Length we extracted from the Survey Shot, we were able to track the Camera very easily, and rather successfully. Because some of you may not be convinced about the usefulness of the Survey Shot, as it requires a bit more effort, let's quickly take a look at what would've happened, had we NOT used the Focal Length from the Survey Shot.

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Transcript

As you saw in the previous video, with the help of the focal length we extracted from the survey shot, we're able to track the camera very easily, and rather successfully I would say. Because some of you may not be convinced, yet, about the usefulness of the survey shot, as it requires a bit more effort, let's quickly take a look at what would have happened had we not used the focal length and tracked the shot with unknown and constant focal length. Let me remind you that the focal length was estimated 34.51 millimeters, and we should expect something close to that in this case. Mind you I'm using exactly the same footage and exactly the same tracking settings. So let me just go here and say full solve. So the solve is finished. Let's select the camera, and take a look at this: 47.773. So this is 13 millimeters more than what was calculated earlier, and I have to tell you it took a bit longer to solve, and that is because there was less information available. Now let me just double click here. Copy this, and I have another document. What you see here is the camera that was estimated. I'm going to make a copy of it by Control dragging, and I'm going to go and activate it. What I'm going to do is paste this number here. Now look at the difference between these two. That's quite a significant difference, and even if we correct for distance, we go and do this, so, let's select this. Move it over here. Let's see. There you go. Look at the difference in perspective. This is what I want you to pay attention to. So the size is similar, but the perspective is different. This amount of deviation in the focal length is going to produce a very wrong result. So I really do hope I convinced you that a survey shot, when available, is extremely helpful to have a very quick, and very successful, and accurate solve for your camera and object.
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