Hi everyone, I’m testing an Arducam camera for a low-light/nighttime project and I’ve hit a wall. The setup is a Raspberry Pi 4 with the camera static the whole night. I set it to take pictures every hour at different exposure levels (from 1000 to 67000) and gain levels (from 0 to 700), full manual control. The lens is a low light 3.5mm F1.8 1/2.5" with the IR filter removed. The sky was clear but there was no moon (northern hemisphere, short nights, so not many shots). The camera performs well while the sun is less than 10 degrees below the horizon, but after that the image is just black. I really need a camera that gives at least some image at ~20fps during the night outside a city environment. Any idea what I’m doing wrong?
Thanks for the detailed info. To help narrow this down, could you share the exact camera model you’re using and a couple of the captured images/videos showing the black frames? Also, when you say outside a city environment with no moon and a clear sky, is there any ambient light at all, or is it truly pitch dark? That makes a big difference for these low-light sensors.
It’s an IMX462 based module. I’m actually comparing two of your IMX462 models right now: the B0496 (2MP IMX462 manual focus USB 3.0 camera module) and the B0444 (2MP IMX462 color ultra low light STARVIS camera module with 141° wide angle M12 lens for Raspberry Pi). Same sensor, different price, so I’m trying to figure out which fits better. For the test conditions: clear sky, no moon, camera static all night. IR light is part of the project, but these tests were done without any IR illumination - I’m going to test with various IR emitters next. But before going down that path, I wanted to confirm whether the sensor itself should be able to see anything in those conditions.
To answer the direct question: even though this sensor has high G sensitivity, a certain amount of supplementary light is unavoidable. In a no-moon, clear-sky night scene without IR illumination, the camera can’t produce a usable image - so the black frames after the sun drops below roughly 10 degrees are expected behavior. I’d suggest adding supplementary IR-LED light to fill the scene for the lens you’re using. Could you also share the captured images/videos showing the failure mode (the black frames with clear sky and no moon)? And if you can describe the application scenario, shooting process, and environment in more detail, that will help us give the best suggestion.
Okay, that makes sense and kind of confirms my suspicion that my testing methodology might have been flawed. I’ll try filling the scene with IR-LED light next. One thing I want to get right though: since I need ~20fps at night, should I go with the B0496 (USB 3.0) or the B0444 (MIPI/CSI for the Pi)? The B0444 is cheaper, but I’m not sure about the bandwidth limits on CSI vs USB 3.0.
Good question. Both use the same IMX462 sensor, so the low-light performance at the sensor level is identical - the difference is the interface. The B0496 is a USB 3.0 camera with plug-and-play support on Windows and Linux, no additional drivers needed, and the higher bandwidth allows more combinations of resolution and frame rate, so it covers more application scenarios. The B0444 is the MIPI/CSI module variant for Raspberry Pi. For your ~20fps requirement either can work, but if you want headroom on resolution/frame-rate combinations, the USB 3.0 module gives you more flexibility. I’ve also sent you a requirements form through private message - if you fill that out as much as possible, our engineers can give a more specific recommendation for your project.
Thanks, I’ll check my messages for the form. Quick follow-up on the IR fill light: is there any guidance on how much IR illumination is typically needed for the IMX462 in a no-moon scene? I’m going to test with a few different IR emitters and I want to make sure I’m not underestimating the amount of light needed.
That depends heavily on the distance and field of view of your 3.5mm F1.8 lens, but the general rule is to light the scene until the sensor gets enough signal - since the IR filter is already removed you’re in a good position. Start with a modest IR-LED source aimed at the area you care about and increase from there; you’ll see the black frames start showing detail once you cross the sensor’s threshold. To summarize where we landed: the black images in no-moon conditions are expected even for this high-sensitivity sensor, and supplementary IR light is required. If you can post back with the test images and the filled-in form, we can confirm the setup and suggest the best fit between the B0496 and B0444 for your use case.