The SJ20 Looks Janky, But It’s the First-Ever Dual Lens Action Camera


The SJCAM SJ20 is the first action camera to feature a dual camera system with separate lenses dedicated to day and night capture. The company promises it will be able to capture “crisp” footage regardless of lighting condition.

SJCAM can capture videos in 4K, 2.5K, and 1080p Full HD as well as photos at up to 20 megapixels of resolution (although it offers the ability to also capture 8, 10, 12, 14, and 16 megapixels). Videos are recorded in the MP4 format and can be encoded as either h.264 or h.265.

4K footage is capped at 30p, 2K footage can be captured at up to 60p, and Full HD capture allows the camera to shoot as fast as 120p.

While the company promises two separate cameras, which presumably would include two sensors behind each as is common with smartphones, SJCAM has not published any detailed information on what size those sensors are, which is never a particularly good sign. Aside from noting that each lens has a field of view of 135-degrees and that one has an aperture of f/2 while the other has an aperture of f/1.3 (for day and night capture, respectively), very little else about the image capture system is explained.

“Users can easily switch between the different lenses depending on the environment and light to ensure the best image capture at all times; even in dim light conditions,” the company says. It does not sound as though the camera can record with both lenses simultaneously.


The dual-lens action camera features multiple capture options including motion detection, slow motion, pre-recording, and timelapse. Theoretically it can connect to a mobile device using 2.4 and 5Ghz WiFi, although SJCAM makes no mention of a companion app.

Design-wise, the SJ20 features two touchscreens. The rear screen measures 2.29 inches while the screen on the front is a much smaller 1.3 inches. Because menu controls are presumably managed via touch, the body of the camera doesn’t feature many other buttons — just two on the top: one for recording and one for activating access to the menu.


SJCAM says the SJ20 is waterproof down to 16 feet without a dedicated case, but with one it can extend that down to 130 feet. It also features what the company describes as a six-axis gyroscope to enable smooth capture.

The SJ20 has a quoted seven hours of battery life per charge, although the company’s marketing doesn’t really explain that the 800mAh integrated battery is only capable of 2.5 hours of 4K recording. To get the quoted seven hours requires using the separate 1,050mAh external battery pack that attaches to the bottom of the camera which costs an additional $20. SJCAM will also release a camera grip that features camera control buttons as well as an even larger 4,800mAh battery which can operate underwater.


SJCAM’s SJ20 is available for $229. Given the fact that the company is inexplicably using some very bad AI-generated photos on its product page and it has not published detailed lens and sensor specifications, healthy skepticism regarding quality is warranted. Even though SJCAM claims footage shot in low light will be better than what GoPro makes, footage from the Hero12 Black is very good. That, and GoPro’s reputation carries significant weight.

That said, the dual lens design is intriguing and it will be interesting to see if it is something that will make its way to more established options like GoPro or DJI. Speaking of the latter, DJI put multiple cameras into a few different drones, so seeing that in an action camera does make some sense.