ZWO ASI 120MM Mini USB 2.0 Mono Camera
 ZWO ASI 120MM Mini USB 2.0 Mono CameraZWO ASI 120MM Mini USB 2.0 Mono Camera 

ZWO ASI 120MM Mini USB 2.0 Mono Camera

  (25 Reviews)
✓ 2 year warranty


45x in stock shipped 1-2 working days

About this product

Model:  zwo_asi120mm_mini
Part Number:  ASI120MINI

Compatible with the ZWO ASiair smiley

The ASI120MM Mini is a very capable guide camera that can easily handle most setups, including most OAG configurations. 

Peak QE of 75% (better than the ICX618) and no Fixed-Pattern-Noise!  

Supports 35 FPS at its maximum 1280 x 960 resolution and long time exposures up to 1000s!  

Compared to ICX618-based cameras, the ZWO ASI120MM offers a faster frame rate, slightly higher visible light sensitivity and more pixels for lunar imaging. 

An anti-reflection clear optical window protects the sensor. If imaging the Moon or planets, we recommend fitting a 1.25" UV/IR rejection filter. 

The ASI120MM’s mono sensor can also be used with specialised UV or methane band filters and infrared passing filters for lunar and planetary imaging (i.e. Baader IR-Pass, Red and Orange visual filters). IR-passing filters cut short wavelengths, which prevents atmospheric dispersion from softening the image. 

Note: The ASI120MM has a Micron sensor which might produce Newton Rings when used with solar telescopes. (Cameras fitted with Sony sensors are better in these circumstances).

Not recommended for use in Linux


  • 1.2 Megapixels, 1280 x 960 pixel 1/3" AR0130CS CMOS Mono Sensor
  • 3.75μm Square Pixels
  • 12bit ADC
  • Peak QE ~75%
  • 4.0e Read Noise, 13000e Full Well
  • ST4 Port
  • USB2.0 Type C
  • Weighs only 60g!


Most popular astronomy magazines have reviewed ZWO ASI120 cameras. Please click the links below to read PDF documents:

All ZWO cameras include a 2-year warranty. 

Camera Field of View Simulator

ASI120MM Mini Astrophotography Performance

The ASI120 mini camera offers very good performance for planetary imaging and guiding. Low read noise, high dynamic range, QE peak of 75%, AR protective window and much more.

ASI120MM Mini QE Curve

Absolute QE Curve, we estimate the Peak Value is over 75%.

ASI120MM Mini vs ASI120MM-S

Compared with the ASI120MM-S camera, the ASI120mini is smaller, lighter, and can reach focus at the same position as an eyepiece.

USB2.0 & ST4 Ports

USB 2.0 Port: The mini camera has one USB 2.0 type C port. Type C is very popular in mobile phones and reversible, so it doesn't matter which way around you insert the plug.

ST4 Port: To connect directly to a mount's auto guide port.

Connection Drawing

  1. M28.5-CS adapter
  2. CS-C adapter
  3. 1.25″ extender
  4. 1.25″ filter

Mechanical Drawing

What's in the box?

What's in the box

  • ASI120MM Mini Camera
  • 1.25" Cap
  • 0.5m USB2.0 Cable
  • 2m USB2.0 Cable
  • 2m ST-4 Cable
  • M28.5-CS Adapter
  • 1.25" Extender
  • Quick Guide


Sensor 1/3″ CMOS AR0130CS(Color)
Resolution 1.2Mega Pixels 1280×960
Pixel Size 3.75µm
Exposure Range 64µs-1000s
ROI Supported
ST4 Guider Port Yes
Focus Distance to Sensor 8.5mm
Shutter Type Rolling Shutter
Protect window AR coated window
Operating System Compatibility Mac, Windows, Linux
Interface USB2.0
Bit rate 12bit output(12bit ADC)
Adaptor 1.25″ / M28.5X0.6
Dimension φ36mm X 61mm
Weight 60g or 3.1 ounces (without lens)
Working Temperature -5°C—45°C
Storage Temperature -20°C—60°C
Working Relative Humidity 20%—80%
Storage Relative Humidity 20%—95%

Supported Resolutions:

Binning 1×1:

  • 1280X960@35FPS
  • 1280X720@46FPS
  • 1024X768@54FPS
  • 800X600@90FPS
  • 640X480@118FPS
  • 320X240@224FPS

Binning 2×2:

  • 640X480@35FPS

Additional resolutions can be user defined.

Downloads / Manuals

The following manuals and downloads are available for this product:


ZWO Software and Drivers


Customer reviews

Average Rating (25 Reviews):  
Write a Review and share your opinions!

Rating (max 5):  
Zwo ASI 120 mm
15 May 2023  | 

Excellent after sales support, second to none, Excellent product, thanks again to the guys at First light was super fast

Rating (max 5):  
11 December 2022  | 

I bought this camera as an upgrade guide camera from my 120mc for better guiding. Excellent camera, works great. Delivery from FLO perfect as always. It arrived nestled in a foam filled box super protected. Thanks Alex and FLO for the great service.

Rating (max 5):  
A good guide camera
24 November 2022  | 

I only bought this to replace my Altair GPCam as the ASIAIR does not support non-ZWO hardware. Works as it should and FLO were brilliant.

Rating (max 5):  
Guide Camera
22 November 2022  | 

Excellent service. Thank you

Rating (max 5):  
Guiding camera
31 August 2022  | 

Great quality and works superbly via my Asiair plus. Provided with superb customer service, as always, from FLO. Thanks

Rating (max 5):  
Zwo asi guiding camera
09 August 2022  | 

The camera works perfectly with my equatorial mount, received in excellent condition, well packed with fast shipping. Thank you to FLO for their professional and quality service.

Rating (max 5):  
Superb sensitivity
17 June 2022  | 

I am using this camera with a small 50mm Orion guide scope (only 162mm focal length). Even with such a small scope, this is guiding my 6" Celestron scope on an AVX mount with excellent tracking. Any tracking errors are much smaller than any disturbances caused by seeing conditions so stars remain sharp on my DSLR even with 3 minute exposures (I could go as long as I want, but 3 mins is a suitable cutoff time for me). Sensitivity with this setup is amazing even with short (less than a second) exposures and never fails to find stars wherever I point the scope.

Rating (max 5):  
ZWO ASI 120MM Mini not just a guide camera.
11 April 2022  | 

I have used one of these cameras as a guide camera and it is fine for this purpose. However I needed a low light sensitive camera to monitor the position of the scopes within the dome to ensure the aperture tracking was accurate. The ASI120 with a ZWO wide angle lens fitted running through SharpCap produces a crisp, zoomable image in near darkness, which can now be monitored remotely, given it is PC based. I notice ZWO now include right angled USB plugs, which put less strain on the connector. Thoroughly recommended.

Rating (max 5):  
Works perfectly with ASIAIR Plus
10 March 2022  | 

Great Service from FLO as usual and this camera works a treat when combined with my WO Guide scope. Connected to the ASIAIR plus (also ordered and fast delivery from FLO) via my ZWO 2600MC Pro on the USB2 Guide port, Iíve managed to focus and get star sizes right down. Sure there is the more sensitive guide camera but itís almost double the price - thereís really no need for the more sensitive version IMO as the 120 does a great job with a guide scope. Maybe Iíll get the more sensitive version if I go down the OAG route but Iíd be using that with a longer focal length OTA than I currently haveÖ Recommended for quality and service !

Rating (max 5):  
Very good for the price
04 February 2022  | 

I have recently started astrophotography and initially I was taking photos without guiding and wasnít able to get above 40 second subs but with the guide camera, PHD and sharp cap my polar alignment is way better and I can now usually get around 5 minute exposures before trailing.

Read all 25 customer reviews...


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