Rolling Shutter Correction - DJI Mini 2

Attempting to use the Rolling Shutter Correction. It says the camera cannot be found. Searching the forums I see references to a “database” of cameras? Where can that be found, if there is such a thing.
If the DJI Mini 2 is not included, can anyone explain how I can calculate the required factor? Maybe an online calculator for speed/height etc.?
TKS

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Check this link out:

Specifically this link that is linked there:

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Great information! May make a good winter weather project!
In the link there is a method to submit the data once done.
On the off chance someone has done this already, how would I find what is included in the db?

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I use the same drone and have also been searching for information about this camera on the Mini 2, but I do not have time to do the recommended experiments.

However since the the Mini 1 and Mini 2 have similar camera specifications, I took a guess that the Mini 2 may have the same rolling shutter parameter as the Mini 1.

I have been using the Mini 1 value of 20 for many datasets, and haven’t noticed any abnormalities.

If accuracy was critical I think I would want to be more sure of the correct value.

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Thanks for the response. I’ll give it a try.
Looking at parts to put together one on a rainy/snowy day, which is sure to be in the near future!
G

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Please let us know if you run into any issues getting the data or submitting it. I am always available to help the best I can.

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I thought mini 2 was in the system with a figure of 26 from memory

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I’m not seeing it, but another set of eyes is always welcome :slight_smile: I’m a bit frazzled these days haha

Definitely not there, but the default 30ms is pretty close.

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Here you go, check this post out Important Feature Update: Rolling Shutter Distortion Correction - #17 by rumenchooo

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Built Raspberry Pi Pico. Added code as given.
DJI Mini 2. 1/8000 shutter. Only see 4 lines.
Slowing shutter it overexposes and I see no lines.
Does that sound possible? Everything else seems to be much higher numerically.
Double checked on/off at “1000 ms” as in code. Took multiple photos, with the red LED get the same, using others do not get acceptable photos. Bright white overexposes so solid white.


DJI Mini Camera Settings

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Ah, I see, it should be the entire frame, not just the LED. Will have to try different settings to see the rest of the frame. So far I have not been able to get bars from top to bottom.
Tips? Bigger LED. More light on the breadboard? I saw an article about putting the LED in a piece of Styrofoam to maybe make it larger.
I’ll keep trying!

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Use the white LED and get it to not saturate: move it away, turn off other lights, etc…

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De-focus to make it fill the vertical part of the frame.

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Okay, I think these will work. I do not know if it makes a difference, but I shot a few frames using the “JPG + RAW” setting in DJI. I obtained different results. If these look good, I will post using the form listed in Github.

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These look great.

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The top one agrees with the figure quoted in the post that I linked to earlier :+1:

I have added this information on the submission page, saw the “Excellent” so hopefully it was saved. I did not do a pull ticket since I am not signed up. If it did not go through, I guess you could maybe just move it.

Some thoughts as someone who tried this the first time.
Might specify the camera settings on submission page, or somewhere. I did some at 16:9 which give totally different readings, numerically lower since I believe the photo is trimmed to get the size. So I think 4:3 (full size of sensor) is what you want?
Also it took quite a bit of fiddling around, maybe my LED was to bright. I ended up shooting through a translucent 35mm film container (remember those?) to even the light out. I saw somewhere about using white Styrofoam, I may try that just to see when I find some thin stock.

This did agree with MartinR’s linked article, but since the information in that post is not listed in the database, I submitted so it can/will be in the future.

G

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One last (?) update on this. I was still unhappy with my results. I purchased a selection of 10 MM Diffused LED’s in different colors. (Just for fun and experimenting.)
I got much better results this way. So I would suggest anyone looking to do this look at those instead of very bright 5 MM LED’s. Same results, but much easier to obtain good photos.

DJI Mini 2 25 Lines Blue (Small)

DJI Mini 2 25 Lines White (Small)
.

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Thanks for doing this and sharing.

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