Hi hlorenzl!
Some clarification... even though there are pages on the web that refer to NDVI lenses, NDVI refers not to a lens, but a type of filter... to pass only the limited bandwidth of light used to do these crop analyses. However, unlike other filters such as ND filters or polarizers, these filters are permanently mounted on the back of the lens, directly in front of the camera sensor. This necessitates that you purchase a separate camera to be used exclusively for NDVI work. So any vendor offering a "NDVI lens", is simply selling you a lens with the filter pre-installed.
If you are going to use the Typhoon H for NDVI work, you will want to install a third party lens. Even if you wanted to use the original lens, the glue that is used on the OEM lens would need to be removed and cleaned before installing the NDVI filter. So at that point, getting the superior sharpness of a lens like the PixAero 3.77 and having a NDVI filter installed at the same time is the most cost effective modification.
I have not yet started my commercial flying, but I intend to incorporate NDVI analysis as part of my offered services. Interestingly, I had bookmarked Peau's NDVI filters page several months ago... on re-checking before posting here, I see that they are no longer offering NDVI filters.
You can also do a search for "UAV Toolbox grid mapping" which will yield threads on previously discussed, upcoming additional functions to Tuna's app... these will be directly applicable to using the H for NDVI work.
Hello Eagle's Eye Video!
Firstly, thank you for the clarification and information. If you are still planning on adding NDVI or other Vegetation Indices outputs (stills, map, and analyses) to your services, maybe we can share our ideas and continue discussions in this thread.
Umm, regarding the terms I've used, thank you for correcting that filters are the ones that "produces" the inputs for making NDVI images and not just the lens itself. But I kinda used the term "lens" because that's what Peau was selling.hehe from what I understand, they actual fixed or "cemented" the filters on their lenses that allows the sensor to only capture NIR, R, G, B, or combination of these like when used in computing NDVI during post processing.
Please correct me if I'm wrong. From what I understand, the light that is reflected from an object is what the camera captures and saves as an image. The regular RGB image that we get is only the captured reflected visible light which is coming from a certain width or range of frequency from the electromagnetic spectrum (somewhere between UV and IR) where our image sensors capture RGB data and record on a specific pixel until it completes the whole map of pixels (or image), while the NDVI is computed only through specific values from a smaller fraction or range in the spectrum (maybe NIR + G, or NIR + B) which is recorded per pixel and is mapped as a whole "NDVI image".
Anyway, the reason why I am saying this is that because of my understanding (not sure if right), it must mean that our CGO3+ can be converted to a NIR camera that can capture the reflected light from the leaf surfaces of crops by buying the lens (with cemented filter) or more simply just a filter like the polar pro filters that can just be placed and replaced every time it's needed. This would be more convenient as this would not require me to buy another CGO3+ just to have the data that I need to compute and make NDVI maps.. any idea if it is possible to have a filter that would only allow NIR or any specific band of light that is needed for the calculations?
Another idea of mine is to add a mounting designed to hold cameras as large as GoPros (particularly the MapIR cameras that have dual lenses and sensors that can capture NIR and RGB data at the same time). I hope someone makes that kind of mounting as the one recently released for the DJI Mavic and Mavic Pro. I'm really jealous on the availability of aftermarket support for DJI..hehe
Anyway, I hope we can continue this thread until we found out what to do to get cheap NDVI images from our TH.
Kind regards