Please help me to solve the question.
I have DJI Phantom 4 drone + I ordered and installed the modified camera from Dronenerds.com. Please see the following link http://www.dronenerds.com/products/ndvi-cameras/ndvi-camera-units/ndvi-phantom-4-camera-unit-ndvip4-ndvi.html As it has been explained by Dronenerds, they sell the camera with RED + Near-InfraRed lens.
I am going to use this camera for creating NDVI maps for my my farmers, but unfortunately nobody can tell what combination of Filter type and Algorithm I need to select in order to recognize the stress spots at my fields. As you can see from the attached pictures, the half of metallic bins and sheds are green and others are red. I am confused. Please help to do the right choice. Thank you in advance.
Kara, thank you, but it’s just a general answers. I have been taking a part in two last webinars and there were also the general answers. I would like to buy a subscription for 3 months on a coming agricultural season, but I do not see real support from Dronedeploy side. I just asked a simple question about “red and green grain bins on the pictures” and you sent me to links, which I have already read before.
So this could be as simple as the reflective properties of the materials used in the sheds. If they have a surface that mimics the reflective light properties of healthy or unhealthy plants you will see that information displayed, do you have a RGB photos of the area, or happen to know what is on the tops of the roofs. For most of the Chlorophyll A that is active in the majority of the plants life you should see increased absorption in red, blue, and NIR/IR frequencies, with reflectivity in the others. Since the material properties on the roof appear to be consistent you can better remove them by adjusting your range of values to not include the extremes [0.29 - 0.1]. As to the filter types you will most likely be best served to export and compare each to find the one with the most reliable data. The algorithm should be NDVI if you are using NIR/IR sensing technology.
Thank you Scott. I have been thinking about this, but should to find like-minded people like you:). I am going right to this farm again and will use my second DJI Phantom 4 with RGB camera and then I would like to compare NIR+NDVI and RGB+VARI. The I will download the results once I get them from DroneDeploy.
Awesome would love to see those results, as i am sure many others will have similar questions. Back many moons ago i ran a Cold Vapor Atomic Absorption spectrophotometer so i have a decent level of knowledge with non visual spectrum detection. Cant wait to see your analysis, as Ag is something i would love to spread my business into, though eastern MA is not exactly farm country.
Please have a look the attached photos. It took my 10 minutes to swap up the cameras. I have done a video for my farmers how they can do it by themselves in home conditions, because they follow my You tube channel and want to improve their skills either. Here is a link https://www.youtube.com/channel/UC8ldhuVLVidEx6XBQCUnBaQ/featured
Please have a look at the same farm, but it’s done by RGB camera+VARI Algorithm. If we compare NIR+NDVI vs. RGB+VARI, then the first one is more accurate, but not way much.
