SJCAM SJ20 Dual Lens vs SJCAM C400
In short: The SJCAM SJ20 Dual Lens costs $20 less.
| Spec | SJCAM SJ20 Dual Lens | SJCAM C400 |
|---|---|---|
| Approx. price | ~$229 | ~$249 |
| Year-one cost | ~$229 | ~$249 |
| Type | Budget action | Budget action |
| Sensor size | 1/2.3-inch | 1/2.3-inch |
| Sensor area | 28 mm² | 28 mm² |
| Max resolution | 4K @ 30fps | 4K @ 30fps |
| Reframed resolution | n/a — already flat | n/a — already flat |
| Max fps at 4K | 30 | 30 |
| Max fps at 1080p | 60 | 120 |
| Max bitrate | 25 Mbps | Not published |
| Colour depth | Not published | Not published |
| Log profile | None | None |
| Stabilisation | 6-axis gyro EIS | 6-axis gyro EIS |
| Horizon lock | None | None |
| Aperture | f/1.3 | Not published |
| Waterproof | 40 m in the case only | 30 m in the case only |
| Claimed runtime | Not published | 7 h 17 min at 4K30 with the 3000 mAh handle attached; 172 minutes on the 54 g camera alone |
| Tested runtime | 2 h 17 min (road.cc action camera group test) | No third-party test collected |
| Battery | Not published | 1250 mAh |
| Cold rating | — | — |
| Weight | Not published | 54 g |
| Screens | Front + rear dual screens | Rotating screen on the handle |
| Mount | GoPro folding fingers | GoPro folding fingers |
| Replaceable lenses | No | No |
| GPS | No | No |
| Voice control | No | No |
| Storage | microSD | microSD |
| Subscription | None | None |
| Released | 2024 | 2025 |
A highlighted cell is the outright better figure in that row, and only where one direction is unambiguously better. Weight, field of view and battery capacity are left neutral because the better direction depends entirely on what you are shooting.
Strengths and drawbacks
SJCAM SJ20 Dual Lens
- +The f/1.3 night lens is a real optical answer to low light, not noise reduction
- +Outlasted the Insta360 Ace Pro 2 by more than half an hour in a same-conditions drain test
- +Dual screens and dual batteries as standard
- +Mounts on the GoPro fingers every clamp and harness is built around
- −25 Mbps ceiling — a fifth of the flagships, and fast motion smears at it
- −4K caps at 30 fps and there is no horizon lock
- −No bare waterproofing; the 40 m case is mandatory near water
- −SJCAM publishes no battery capacity or weight
SJCAM C400
- +Over seven hours at 4K30 with the handle, the longest figure in this catalogue
- +54 g module is lighter than a GoPro HERO and close to an Insta360 GO 3S
- +Rotating screen makes it usable for talking to camera
- +Half the price of the DJI Osmo Nano and Insta360 GO Ultra it copies
- +The camera module drops into the handle without a cable, so the changeover takes seconds
- −1/2.3-inch sensor — roughly a quarter of the Osmo Nano's imaging area
- −No bare waterproofing at all
- −4K30 only, no horizon lock, no log profile
- −The module has no screen of its own; framing needs the handle