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Bending horizon when pointing gimbal down?

swoermck

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Hi,

I watched many Youtube videos with footage from the Mavic Mini so far (can only watch as FlyMore combo still not available in Switzerland), but one thing I noticed in many videos:

- when pointing the gimbal down, so the horizon is in the upper part of the picture, it seems that in the far left and right edges it looks like the horizon is not straight, like bending downwards towards the edges?

I just watched this video


and if you play from 0:28 it's quite obvious - and also getting better as the gimbal is pointing up again (= horizon again in the middle of the picture).

Is it a know limitation of the lens when pointing down or maybe just an issue of first lot of the Mavic Mini? Never seen this in the footage of my Mavic Pro 1...?

Stefan
 

old man mavic

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probably as it lowers down it changes the focal length slightly, and gives the impression that the outside edges at the top of the picture are bending downwards not a camera expert just my take on the issue
 

swoermck

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Did you experience this "bending" in your footage as well?

just found another example:


if you pause the video at 1:25 it looks even worse..

both samples I found are in 1080p (at least the version on youtube) - maybe better in 2.7K 🤔??
 

slup

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Hi,

I watched many Youtube videos with footage from the Mavic Mini so far (can only watch as FlyMore combo still not available in Switzerland), but one thing I noticed in many videos:

- when pointing the gimbal down, so the horizon is in the upper part of the picture, it seems that in the far left and right edges it looks like the horizon is not straight, like bending downwards towards the edges?

I just watched this video


and if you play from 0:28 it's quite obvious - and also getting better as the gimbal is pointing up again (= horizon again in the middle of the picture).

Is it a know limitation of the lens when pointing down or maybe just an issue of first lot of the Mavic Mini? Never seen this in the footage of my Mavic Pro 1...?

Stefan
Not surprising ... probably the lens have a slight Barrel distortion & the distortion is always worse in the edges.
Read more here for instance --> Lens Distortion: What Every Photographer Should Know | Click it Up a Notch®

Either the lens have Barrel or Pincushion distortion ... or in some rare cases a mix.



If straight lines are positioned either horizontal or vertical in the middle they remain straight ... but to the edges they bow like in the pic above. When it comes to the Mini lens mentioned in earlier posts DJI have managed to make the lens more flat reflecting in the middle section but then it bows away. It's only lenses for $$$$ that are nearly free from distortion.
Distortions from lenses can somewhat be corrected in post by means of special profiles either loaded up in the editing program or in some cases they are attached in the video/photo file itself.

And just to have it said ... lens distortion doesn't change depending on resolution, it will remain the same weather you film in 1080p or 2.7K.
 

swoermck

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Either the lens have Barrel or Pincushion distortion ... or in some rare cases a mix.

Just watched more videos, and it seems to me a combination of barrel (towards the edges) and pincushion (in the middle).

For removing them in post: I use Davinci Resolve for colorgrading (for Mavic Pro 1), would Davinci work for removing distortion as well?

Never touched this area before (as it was not necessary so far for the MP1).

thanks,

Stefan
 

fRog2

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Just watched more videos, and it seems to me a combination of barrel (towards the edges) and pincushion (in the middle).

For removing them in post: I use Davinci Resolve for colorgrading (for Mavic Pro 1), would Davinci work for removing distortion as well?

Never touched this area before (as it was not necessary so far for the MP1).

thanks,

Stefan
Barrel distortion would be normal for any wide angle lens. There will be correction done in the drone camera itself (it would be interesting to see RAW images from it without the processing), which is probably why you are seeing what appears to be a mixture of barrel and pincushion - they will be trying to correct the image without using too much processing effort.
 

Chris Baish

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Just watched more videos, and it seems to me a combination of barrel (towards the edges) and pincushion (in the middle).

For removing them in post: I use Davinci Resolve for colorgrading (for Mavic Pro 1), would Davinci work for removing distortion as well?

Never touched this area before (as it was not necessary so far for the MP1).

thanks,

Stefan
This was exactly the same on the Mavic Air. Pinched in the middle and barrel at the edges. Some people seem to notice it more than others, but for me it ruined it. Look back at some Mavic Air videos and once you've noticed it you can't un-notice it unfortunately.
 

swoermck

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This was exactly the same on the Mavic Air. Pinched in the middle and barrel at the edges. Some people seem to notice it more than others, but for me it ruined it. Look back at some Mavic Air videos and once you've noticed it you can't un-notice it unfortunately.
I remember those discussion about the Mavic Air (and recognized it as well in a video a friend did with his Mavic Air) - one of the reason why I didn't go for the Mavic Air those days and sticked to my good old MP1. By the way: was that ever fixed for the Mavic Air?

Now let's hope that DJI will fix this for the MM in future firmware updates..

.. no rush for me to go for Mavic Mini now: the "magic" 249g won't change things in the future here in Europe, although upcoming drone regulations from the EU will honor the 250g limit, but:

"If, however, the drone is lighter than one of the above criteria, but is equipped with a sensor able to capture personal data (e.g. a camera), the drone operator must still be registered."

So whether MP1 (700g) or MM (249g) - with the upcoming EU laws both birds have to be registered...

But the small package of the MM is still appealing to me (e.g. when hiking, biking etc.)
 

swoermck

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Distortions from lenses can somewhat be corrected in post by means of special profiles either loaded up in the editing program or in some cases they are attached in the video/photo file itself.
Meanwhile I found a link here for a tutorial how to remove lens distortion:


seems to be the solution to correct MM footage as well Thumbswayup