Barrel Distortion Resolution
689 5 2019-10-21
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instadrone
lvl.1
Canada
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Hello,

When shooting in D-Log on Mavic 2, obviously you need to apply barrel distortion fix. When you do this, you're video resolution shrinks, since the software process needs to cut off the edges and then stretch the result into a full 4k resolution.

First this seems very odd, since now the video, especially the corners are no longer in 4k resolution... more like 3.8k stretched into 4k canvas.

My question is, on the regular video mode, does the drone do the same thing, just using its own processing firmware?

If thats the case, then how can this be considered a 4k video?

in HQ mode, you're using a portion of the sensor, so why not shoot a video HIGHER than 4k (use a little more of the sensor), so that after applying the distortion fix, you end up with actually a true 4k resolution?

Thanks,

2019-10-21
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izotop
lvl.4
Flight distance : 388763 ft

Slovenia
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in reality, true optical resolution of m2p (especially in ff mode) is not 4k, more like 2,7k (imo), but this goes similar for all drones or cameras out there, since it's related to optics quality, sensor image processing etc. if you don't have top notch image to begin with, it's not worth applying billions of pixels of resolution, since you're not gaining anything from it, just more blur.
but in the other hand, 4k video in crop mode is sharper than 4k video in ff, so lens could cope with it, i guess. They only need to reastablish all pixel reading in ff, but this won't happen, since it's been asked from day one..
2019-10-22
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instadrone
lvl.1
Canada
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I'm not sure what you mean. The sensor has pixels. 4k is 3840x2160 pixels. The light cone covers the WHOLE sensor, meaning that each pixel is getting light. even at HQ mode, when its using a portion of the sensor, its TRUE 4k.. meaning that EACH pixels gets unique information. the reason they cut it off in HQ mode is because you get exactly 3840x2160 coverage. When using the full sensor, there are more pixels than required for 4k, so they they use an algorithm to shrink the resolution down to 4k, thats where u loose a bit sharpness...

My beef though is after capturing 3840x2160 pixels, after applying distortion, you end up STRETCHING a smaller video size dimension INTO 4k..
2019-10-22
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instadrone
lvl.1
Canada
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but in any case, even if the optics do not resolve up to 4k as you suggest, no matter what you get originally, you end up STRETCHING even more after distortion correction..
2019-10-22
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DanielVieira
Second Officer
Flight distance : 4633533 ft
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Portugal
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HQ mode also have distortion, you have to fix it in post to....less but its there!
2019-10-22
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Ex Machina
First Officer
Flight distance : 1806362 ft
United States
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Many modern interchangeable lens cameras do this as well with embedded lens profiles -- it's a cost/benefits compromise that has an undetectable effect on the resultant image quality.
2019-10-22
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