The red edge refers to the wavelengths between approx. 0.7 and 0.8 µm, the region between the red, where reflectance from green vegetation is very low and the near infrared where the reflectance is very high.

Now, there are sensors which record wavelenghts within this spectrum like e.g. Sentinel-2 which has bands at 0.705 and at 0.74 µm. The information gives deeper insights in the biochemistry of the leafs as the reflectance in this spectrum is sensitive e.g. to the chlorophyl content. See for example this poster for getting an impression what can be done with this information: http://old.esaconferencebureau.com/docs/12c04_docs2/poster1_18_clevers.pdf

If your drone camera records in this spectrum, you can use this information for example as proxy for the chlorophyl content of the leaves. But the interpretation depends of course also on the scope of your study.

The red edge refers to the wavelengths between approx. 0.7 and 0.8 µm, the region between the red, where reflectance from green vegetation is very low and the near infrared where the reflectance is very high.

Now, there are sensors which record wavelenghts within this spectrum like e.g. Sentinel-2 which has bands at 0.705 and at 0.74 µm. The information gives deeper insights in the biochemistry of the leafs as the reflectance in this spectrum is sensitive e.g. to the chlorophyl content. See for example this poster for getting an impression what can be done with this information: http://old.esaconferencebureau.com/docs/12c04_docs2/poster1_18_clevers.pdf

If your drone camera records in this spectrum, you can use this information for example as proxy for the chlorophyl content of the leaves. But the interpretation depends of course also on the scope of your study.

I agree with Betz that "The red edge refers to the wavelengths between approx. 0.7 and 0.8 µm, the region between the red, where reflectance from green vegetation is very low and the near infrared where the reflectance is very high."

Florian is right.  Here is a paper where we used the red-edge.

https://www.researchgate.net/publication/231584076_Exploring_field_vegetation_reflectance_as_an_indicator_of_soil_contamination_in_river_floodplains

Article Exploring field vegetation reflectance as an indicator of so...

Hi Muharrem,

I have been working with optical imagery acquired with UAVs for application in vegetation monitoring. On the attached publications, we have briefly discussed red-edge features. Hope it can help.

Regards

Conference Paper Estimation of the spectral sensitivity functions of un-modif...

Article Commercial Off-the-Shelf Digital Cameras on Unmanned Aerial ...

It sounds like you purchased a Sequoia. At the distance you are sensing (not proximal), the red edge band will be sensitive to chlorophyll content but it will also be sensitive to leaf angle and leaf area. There are ways to combine red edge with one or more bands in order to reduce sensitivity to leaf area and focus more on chlorophyll content, such as using a "combined index". At that point the interpretation is more straight forward but you will still be left with a map that shows spatial variation in a symptom or limiting factor, such as disease severity or nutrient deficiency.

Muharrem,

All above provided you accurate definition and Florian gave the most complete one. The red edge is specially very useful for plant stress condition and nitrogen content as well. Few days ago, I read a paper and share it with as it has many good indices that may be useful for you for interpretation your data.

Article Using the red-edge bands on Sentinel-2 for retrieving canopy...