What I want to do
I'm an agronomist, I'm going to make a IR RaspiCam to do an IR Timelapse in greenhouse. I want add same sensors (temperature, moisture, soil moisture) at the IR Raspicam in order to link environmental condition to Health of the plant.
My attempt and results
I just took some (BAD) pictures as IR test
Questions and next steps
Hi! I'm going to take same IR pictures by NoIR modulo cam and blue filter (Roscolux #2007: Storaro Blue) in order to measure the health of plants. To take a Picture I'm using "Raspistill". According to this information https://publiclab.org/notes/warren/08-15-2013/white-balancing-a-canon-camera-for-infragram-photography I need to set white balance pointing a deep blue surface before take a IR picture of the plants. I didn't find any custom white balance command in the list of commands of Raspistill. How do I set a custom white balance?
Thanks in advance
best regards
Why I'm interested
1) Learn more about IR Images of the plants 2) to identify by IR Images of the plants best of growing condition or the moments of the worst health of the plants during their growth 3) to use IR Raspicam on aerostatic baloon
LaPa,
The custom white balance procedure you refer to works only for certain cameras. A year ago it was not possible to set a custom white balance on a Pi camera, and I have not heard that this had been implemented. So it might not be possible to set a custom white balance. That means it probably will not be possible to compute NDVI directly from the values in a photo taken with a Pi camera. It might be possible to adjust the values in the photo, but I have not had any success doing that with other cameras.
If you use two cameras, a Pi Camera and a Pi NoIR, custom white balance is not required.
Another approach will be to include calibration targets in the photo you take and use the new calibration capability of the Photo Monitoring plugin for Fiji to compute NDVI from your photos.
There is a discussion related to this here: https://publiclab.org/notes/warren/10-27-2011/video-tutorial-creating-false-color-ndvi-aerial-wetlands-imagery#c12966
Chris
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