Correct focal lengths for Mavic 4 pro

[David Xu]

Would someone confirm the proper focal lengths for the Mavic 4 Pro?

When stitching a panorama taken with a Mavic 4 Pro, I noticed that PTGui uses 14.4mm and 40mm reticular focal lengths, corresponding to the camera's crop factors for its 1x and 6x lenses. In contrast, it lists 28mm and 168mm lengths from the EXIT data.  Could someone explain why PTGui uses different numbers, and are the focal lengths it uses correct? 

Thanks!

David   

[Erik Krause]

Am 17.11.2025 um 23:45 schrieb David Xu:

> When stitching a panorama taken with a Mavic 4 Pro, I noticed that PTGui
> uses 14.4mm and 40mm reticular focal lengths, corresponding to the camera's
> crop factors for its 1x and 6x lenses. In contrast, it lists 28mm and 168mm
> lengths from the EXIT data. Could someone explain why PTGui uses different
> numbers, and are the focal lengths it uses correct?

The EXIF data contains, what the camera writes into it. PTGui uses it as
a hint, but the focal length doesn't say anything about the image
geometry without the corresponding sensor size.

Internally, PTGui uses the Field of View, and this is optimized during
the stitching process based on the actual image geometry determined from
the overlap.

So don't bother too much about the correct focal length. If you shot
with enough overlap (20-30% is sufficient) and there are only minimal
parallax errors, PTGui will determine that Field of View from the
images, that renders the best fit for them.

If, on the other hand, PTGui optimizes the focal length to weird values,
this might be an indicator of severe parallax problems.

--
Erik Krause
http://www.erik-krause.de

[David Xu]

Clear and thanks!!!

David 

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