Fisheye Distortion

Discussion in 'Tips, Guides and Tutorials' started by Jason, Dec 1, 2017.

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  1. Jason

    Jason Moderator

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    As questions about lens distortion pop up often I've put this into it's own thread to explain how it works.

    A fisheye image like this
    StillRawCap_0005.jpg

    would be transformed into a pin cushion image like this
    StillRawCap_0005_01.jpg
    then cropped down to this (note that even if it is saved at the same resolution, the sides of the image is cropped off and the sharpness of the image will suffer)

    StillRawCap_0005_03.jpg
    To get more of the image turn off distortion correction and use fisheye correction in post then crop and letterbox

    StillRawCap_0005_04.jpg

    Because the image has been stretched and pixels moved around, some of the pixels need to be recalculated. There are different formulas for this calculation some faster, but not as good and some slower but better results. As it has to do this real time multiple times a second, doing it in camera may not give the best and sharpest results.

    Distortion correction may be best done during post-processing where you can use the (hopefully) more powerful processor on your computer and when processing in realtime isn't necessary. This way not only can you use a better interpolation algorithm but can reframe the image to get the best result.
     

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    Last edited: Jan 27, 2018
    Troy likes this.
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