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I've recorded some footage using my iPhone 11 Pro that I want to track. Using Google I found that the primary lens (the one I used) has a focal length of 26 mm. However, I understand that for proper tracking I also need to know the Sensor Width and lens distortion values (K1, K2, K3). I've found some articles that explain how to calculate them, but that's quite a lot of work. Has anyone already calculated these values? Pretty strange that Blender 2.90 doesn't come with presets for recent iPhones. After all I think they're one of the most used 4K 60 fps cameras.

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    $\begingroup$ Since the phone allows to zoom, K values are different per zoom factor. $\endgroup$
    – brockmann
    Oct 9, 2020 at 13:11
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    $\begingroup$ Does this answer your question? How to determine lens undistortion values for motion tracking? $\endgroup$
    – brockmann
    Oct 9, 2020 at 13:11
  • $\begingroup$ I have to agree. Iphone 5 is the most recent one on my version of Blender (2.81a) $\endgroup$
    – Strawberry
    Oct 9, 2020 at 13:16
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    $\begingroup$ If you know the lens size, and sensor size you can make your own preset and save it. To calculate the distortion values use the tools in blender (it is hard to do with external tools). Note that there is no way for you to use the distortion values from other phones, as distortion coefficients are unique to each lens. Distortion coefficients will also be different if the lens is zoomed in. You would need to calculate distortion for different focal lengths. Once you find the distortion coefficients for one lens, you can use those numbers for any shot made with that lens. $\endgroup$
    – susu
    Oct 9, 2020 at 16:45
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    $\begingroup$ The very first result of a search for "Iphone 11 sensor size" results in this:. The 4.25mm wide angle lens (26mm FF equivalent) and the sensor size is 1/2.55″ $\endgroup$
    – susu
    Oct 9, 2020 at 20:46

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