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Infragram kite mapping at Fab10 Barcelona

by warren | | 2,365 views | 12 comments |

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I held two workshops at Fab 10 ( where we launched an Infragram Point & Shoot (a modified Mobius Action Cam) above the D-Hub and next to the Torre Agbar, which was pretty photogenic.

Camera setup

I'd gotten it running with a timer and custom white balance using the config file Mathew posted (see instructions here) but I'm not sure the white balance was working for these flights, as there's a strong red tinge to the photos. Perhaps very bright sunlight needs a different white balance, or perhaps for some reason the white balance was just not registering? I used option #8 as Mathew suggested for this batch of cams, so maybe i need to try a few others, but it had been working all right on the ground that morning.

Lens distortion

Apparently (according to some folks from Asturias who joined me on one of the flights) you can purchase a different lens for the Mobius, but the fisheye is nice in that you get large areas. But it'd be nice to remove the distortion, perhaps as part of MapKnitter? This article describes the fisheye lens equation and has some Java code... maybe we can port it to JavaScript.


In any case, here are Infragrammar-processed images, although i boosted the contrast and NDVI values in both:





And some of the amazing raw images we got. Notice especially the second-to-last showing a temporary structure built by Dani Ibañez and others, and the final photo showing the Sagrada Familia, albeit from a distance!










HI warren. We tried to edit our photos on infragram so that they look just like yours, but it didn't work.. Can you please contact us? thanks, GreenLeaves. here is one Image with white balance and blue filter, which we tried to edit. b2.JPG

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This is definitely not the right config setting-- the setting should be : Red Gain=[310],Green Gain=[500],Blue Gain=[700];

Oh hmm... The config file you posted shows

Customized White Balance 1 Red Gain=[310],Green Gain=[500],Blue Gain=[700]; 
Customized White Balance 2 Red Gain=[580],Green Gain=[500],Blue Gain=[350]; 
Customized White Balance 3 Red Gain=[400],Green Gain=[320],Blue Gain=[260]; 
Set red ,green,blue gain,256 is 1x gain,value from 100 to 999;

So which is a value of 8 using? Thanks!

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Custom WB 1 is value 6, WB 2 is 7, WB 3 is 8. But... I found that on my camera the numbers were offset, so 6 was 7, 7 was 8, 8 was 9....

Our problem is, that when we type in the RGB gain numbers and then click "run", the image disappears.. are you familiar with this problem?

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Hi, GreenLeaves - sorry, we were talking about the camera settings, not the stuff. I'm actually traveling so I apologize for not responding faster to your inquiries.

I tried uploading your photo (above) to, and you're right that it does not seem to differentiate plants well. What kind of camera is it? This is what I got with the "basic" colorized preset for blue filters:



I am still traveling until Sunday so please forgive if I am unable to respond quickly. My suspicion is that you may be using a CMOS camera which may work better with red filters, if you read some of cfastie's recent work on the subject. We are thinking of completely switching to red filters in upcoming versions of the kit.

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Hi warren, many thanks for your response. Sorry for disturbing you on your journey. In fact we have a more basic technical problem. After uploading our photograph we can't edit it, as mentioned in our comment earlier today. Might it be an incompatibility with our computer?
We also wanted to edit the photos manually using GIMP, but we couldn't find any useful guideline how to do it.. Could you give us support? -GreenLeaves

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@GreenLeaves, can you share a link to the image as you've edited it so I can see the edit history log? What equation are you trying to use?

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@warren: good news! We solved our problem by downloading a different browser; now it works. But thanks anyway :-)

Great to hear!

@mathew, I fixed it by using WB #7 and setting all 3 to be 310/500/700. I guess that's not good for figuring out the problem but it definitely worked.

Much better -- this one in Bilbao, with @pablo (pablo rey):


nice shot!

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