1

I'm working on a remote (off grid) nest box monitoring project, which should be both low-cost (volunteer-funded) and low-power. No video streaming required, only a snapshot over mobile network every 24 hours (deep sleep most of the time). Looking for 100+ days on one set of batteries to avoid disturbing the location during the nesting season - target current < 1 mA during the sleep period.

High level architecture:

  • ESP32-based board (or similar)
  • 2G/LTE module (depending on coverage)
  • camera module (this is the big question...)

Ideally this would be at least 2 Mpix module providing JPEG output over a serial interface, with no IR filter and an M11 lens mount (or similar) and support for a sleep/power down mode so that no extra circuitry is needed to cut the power for the camera module; price range of about 20 USD/EUR.

There's a number of CSI/MIPI modules for Raspberry Pi and the like, or various USB UVC cameras, but options for microcontrollers are pretty limited.

Most of the time, I'm seeing parallel camera modules (18/20 pins) based on either OV7670 (300 kpix) or OV2640 (2Mpix) sensor (poor image quality, but if there was a no-IR filter version of these, it would be OK considering the price of about $4). If there was a camera module with the same image quality as the Pi Camera v1.3 (5 Mpix) or something like Sony IMX323 (2 Mpix) that would be a much a better choice.

The module that is closest to the requirements is probably the SPI/I2C Arducam, OV2640 version at $26 / OV5642 version at $40. This is using a combination of I2C (config) and SPI (data) 8pin interface, has M12 lens mount and no built-in IR filter but at a higher cost.

Side note: we're already using an "offline" monitoring system (nest locations are visited by someone who connects a cable to a portable monitor and takes a snapshot) with AHD CCTV cameras (e.g. Sony IMX323 CMOS sensor). These are really great when it comes to image quality and low-light sensitivity, and available at a reasonable cost of about 13 €. If there was a similar camera with a digital output, that would be great, but so far I was unable to find something like that (other than the USB UVC or MIPI cameras).

Any ideas on a suitable camera module are welcome. Or if you believe that the overall architecture is wrong and this would be easier to achieve with a more powerful configuration (using something capable of handling a USB UVC camera) that's of course a welcome input as well. For handling the low power operation though, it would probably require a low power microcontroller with RTC to power on the Pi only when needed, so this would increase the cost/complexity of the project. Or maybe it would be possible to handle USB UVC on ESP32 using bit-banging or an external USB host? Not sure if this is feasible at all.

5
  • you could try posting a question at photo.stackexchange.com ... most of your post is kind of irrelevant to the question about a camera ... all you really need is to find a camera that can power down, or sleep and is able to communicate over an interface that involves only a few wires, such as I2C
    – jsotola
    Feb 2 at 23:14
  • @jsotola while I agree that the OP is not looking for something super complicated, photography's scope is much more centered on the artistic and technical aspects of photography rather than barebone chip recommendations and connection protocols for IoT projects... I have a feeling IoT may actually be the best shot at getting an answer.
    – anonymous2
    Feb 3 at 3:49
  • 1
    I see that m5stack have several esp modules using the ov3660 3MP camera from $12 up, a b c, but they presumably have an infrared filter in place. Some people have managed to remove such filters, but it seems a delicate operation.
    – meuh
    Feb 3 at 8:17
  • @jsotola thank you - while there are certainly technical aspects to photography, this seemed to be more of a hardware question than a photography question... I wasn't sure about the right stackexchange site for this really (also considering electrical engineering, arduino, among others) but ended up choosing IoT beta so hopefully this is not completely off topic here :-)
    – Rado
    Feb 3 at 9:48
  • @meuh thank you for pointing out m5stack - they seem to have a nice range of modules, I'll give it a try
    – Rado
    Feb 3 at 9:49

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Browse other questions tagged or ask your own question.