Question: Correct Config. File & Trobule shooting2

will123 is asking a question about infragram
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by will123 | September 29, 2016 01:28 | #13505

What I want to do

I want to verify my mobius camera is taking the correct type photos

My attempt and results

My results show a reddish hue to my photos, however, vegitation does appear pastel/blue

Questions and next steps

Where is the home directy located to store the config file? Is it on the SD card?

Why I'm interested

I want to use MATLAB image processing to advance NDVI into further detail, and identify areas of low photo synthesis on individual plants. I want to tell which parts are doing well, and which are not to a very fine accuracy.


Yes, the config file goes on the SD card.

NDVI is based on the proportion of red to NIR light reflected from leaves. That proportion depends in part on the proportion of those colors in the incoming light. So it works best in normal outdoor light.

Variables such as the angle of the leaves, shadows, clouds, and time of day will alter the NDVI values, so distinguishing subtle differences in plant health requires the careful control of these variables.

Your photo (which is not displaying in the note) produces reasonable NDVI values if 50 is added to the DNs in the NDVI image produced by Fiji (that's equivalent to an increase in NDVI of 0.4). To produce reasonable NDVI values directly from a photo:

  • use a custom white balance appropriate for your lighting conditions
  • take the photos in outdoor light
  • expose the photos well (not too dark or too light)



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