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NDVI option not available?

I just tried my first project using MME using data I collected using a modified camera and Infragram blue filter. I must say I am impressed with the quality of the stitching and elevation and 3d mapping given the quality of the data I uploaded. I was under the impression that one of the outputs would be an NDVI render of the image colour mapped to the scale chosen during the workflow routine. However, after the processing was completed, I find no link or description of any NDVI option.
What am I missing?
Or am I now required to post process through the Infragram sandbox?


Official comment


We just checked the logs and it appears that your job didn't get posted as an NDVI job. It is possible that you hit "Close" instead of "Save" on the NDVI dialog which will cause the "Process as NDVI" checkbox to become unchecked. We will try to address this in a future release, but for now the NDVI isn't showing up because the NDVI settings likely were not saved properly.

Your stitch actually looks pretty good, but I wouldn't expect your NDVI results to be correct anyway. There are groups/companies out there that have been telling people that by collecting more IR and less blue, you can accurately discern crop health. Without a proper calibration and scientifically based "white balancing", you can't get REAL NDVI numbers. The normalized ratio processing can only be done accurately when there is proper separation between the collected wavelengths.

There is a reason that TetraCam and MicaSense cameras cost multiple thousands of dollars. These cameras are properly built to collect data that is sufficient for comparative spectral analysis. Throwing a blue filter in front of a normal Bayer pattern sensor and removing the IR blocking filter is not enough.

The processing that Maps Made Easy applies on it's NDVI processing is strictly in accordance with the published works. If your white balance is off, you can do a little bit of trial and error with the color map to get it to show up to your liking, but that doesn't change the fact that the raw data isn't correct.

Sorry to be the bearer of bad news, but there is so much bad information out there regarding this topic it is crazy...

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I have a DJI Inspire 1 and when I purchased my drone I had the intent of using dronedeploy at that time for NDVI mapping. The dealer I used stated obviously you can't map true NDVI with an RGB camera but they did sell a NIR converted X3 camera to mount on the inspire 1 which would get me NDVI on dronedeploy. The images with the filters installed are orange whereas on MME it asks are the plants "blue or pink/magenta." Is there any true capabilities of this converted camera or it is part of the false information floating around? 

Brett 1 vote
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That is exactly the problem with them. Sometimes the exact same vegetation will come out as orange or pink depending on the available lighting conditions. If you don't have an incident light sensor to sort that out you are just taking funny colored images that don't mean much. 

Zane 1 vote
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