ZWO ASI120MM Mini Mono Guide Camera

Reliable Guiding with 80% Peak QE

A guide camera's primary job is to detect stars, and the ASI120MM Mini's monochrome sensor does this with high efficiency. With a peak QE of 80%, the ON Semiconductor AR0130CS sensor gathers a high percentage of incoming photons, allowing you to use shorter guide exposures and track fainter stars. Combined with a low 4.0e read noise, the camera produces a clean signal-to-noise ratio, preventing your guiding software from losing the star and ruining a long-exposure sub.

Planetary and Lunar Imaging at up to 224 FPS

While designed for guiding, the ASI120MM Mini is a capable planetary imager. The 1280 x 960 sensor is an excellent match for capturing the full disk of Jupiter or Saturn with most long focal length telescopes. For higher-magnification work, you can use a smaller region of interest (ROI) to dramatically increase the frame rate—capturing at 118 FPS at 640x480 resolution allows you to freeze moments of steady seeing, a technique known as "lucky imaging." The camera's USB 2.0 interface provides ample speed for this purpose, simplifying cable management and power requirements.

ASI120MM Mini vs. ASI120MM-S: A Focus on Guiding

The ASI120MM-S has a speed advantage for planetary work due to its USB 3.0 interface. The ASI120MM Mini, however, is purpose-built for guiding with a superior physical design.

• Form Factor: The Mini's 36 mm diameter, 1.25" eyepiece-style body slides directly into any off-axis guider (OAG) or guide scope. The square body of the -S model can cause clearance issues with some focusers and filter wheels.
• Weight: At only 0.2 lb, the Mini adds negligible weight to the imaging train, making it easier to balance your mount and putting less strain on the focuser.
• Focus Position: The Mini is designed to reach focus at the same position as a typical 1.25" eyepiece, simplifying setup. Its 8.5mm native back focus and long body provide a greater focus travel range, making it easier to achieve simultaneous focus with your main imaging camera when used in an OAG.

Integrated ST-4 Port and USB 2.0 Power

The ASI120MM Mini simplifies your setup by drawing all power directly from the USB 2.0 port, eliminating the need for a separate DC power supply. The built-in ST-4 port allows for a direct, reliable connection to your equatorial mount's autoguider input. ZWO includes all necessary cables—a 2-meter USB cable for reaching your control computer, a shorter 0.5-meter cable for connecting to an ASIAIR, and an ST-4 cable—so you can start guiding right out of the box.