Hi

I'm thinking of using an ESP32-CAM for airborne NDVI. This module has a 2M pixel camera, a 32-bit microcontroller and an SD card socket. It weighs less than 10g and is readily available for about $10

It should be possible to remove the IR blocking filter and add an external red filter. Please does anybody have experience of using the ESP32-CAM for NDVI monitoring applications?

Thanks. Mike.

Since posting the above I have been able to remove the IR blocking filter and add a red filter. Obtained some 'interesting' results using Infragram but need to more fully understand what each of the many OV2640 setting options does. Anybody know where I can find this documentation?

Hi @boulax @mfb @mimiss I know this thread is a little old, but I've done a little experimenting with the esp32-cam in relation to ndvi processing. The ov2640 sensor is a great candidate for this purpose as it has an equal response in the 850ish nm IR range to it RGB range. I guess this isn't a deal breaker but it makes the calculations a little more straightforward especially when using two sensors with two different lens filters.

For different images settings there is some documentation here, from GitHub user Raduprv ;

and here;

Compared with the v2 RPi cameras, its results have been less noisey, at least from my experience. The drawback is the image quality, which is pretty terrible, and I have unexplained shadows on one side of both my ESP cameras. Every sensor manufacturer seems to have different lenses, quality, sizes (m6,m7, ect..) and some have no ability to remove the ir filter. So now I'm experimenting with m12 mounts and lenses to try to improve image quality, which also enables more options.

Also the esp32-cam has limited leftover pins available, which means I couldn't use an external trigger to capture an image to the sd card. At the moment, I use HTTP_POST and send an image to a server with no sd card required, however this requires a good wifi connection and lower res images(at least without further experimenting) and could potentially be less reliable.

Anyhow, it remains a low cost and readily availably option that I feel definitely has potential.

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https://www.ebay.ie/itm/155859834544