ZWO ASI294MM Pro Cooled Monochrome Astronomy Camera

Compact Micro-4/3 Astronomy Camera for Deep-Sky and Solar-System Imaging

With a resolution of 11.7 megapixels and read noise of 1.2e, the ZWO ASI294MM-Pro monochrome camera delivers a high signal-to-noise ratio for imaging deep-sky objects.  The ASI294MM-Pro is the monochrome version of the ASI294MC-Pro, one of ZWO’s most popular astronomy cameras. It has the same micro-4/3 sensor dimensions as the ASI294MC-Pro, with a 23.2mm diagonal.

State-of-the-Art Sony Micro-4/3 Sensor

ZWO engineered the ASI294MM camera around Sony’s IMX492, a 47 megapixel sensor with 2.3 micron pixels. It's configured to operate the sensor in a 'Bin2' mode that delivers an effective pixel size of 4.63 microns and a effective resolution of 11.7 megapixels (4144 x 2822). In Bin1 mode, pixels have a 66000e full well capacity, more than 3x the capacity of the ASI1600-series cameras to help you capture sharp images of bright stars without saturation. The sensor has a high estimated QE of 90%, higher than the color version of this same camera, and even higher than the ASI1600MM-Pro. 

The ASI294MM-Pro has a unique feature that allows the user to switch the effective pixel size to an 'Unlocked Bin1' mode in software. This changes the effective pixel size to 2.3 microns and the resolution to 47 megapixels (8288*5644 resolution) with a 14k full well capacity and 12-bit operation.

The dimensions of the sensor matches well for many imaging applications with a wide range of telescopes. A small telescope with 400mm focal length, for example, gives a field of view of with this camera of 2.7 degrees x 1.9 degrees. A telescope with 1500mm focal length gives a field of 0.7 degrees x 0.5 degrees.

Backlit Sensor Technology

The back-illuminated IMX492 sensor improves sensitivity and reduces noise reduction while retaining the advantages of CMOS such as low power consumption and high-speed operation. With a conventional front-illumination structure, the metal wiring and transistors on the surface of the silicon substrate impede photon gathering by the photodiodes. The back-illuminated structure increases overall sensitivity of each pixel because the metal wiring and transistors are on the other side of the silicon substrate. The peak QE of the ASI294MM-Pro is estimated to be 90%.

DDR3 Memory Buffer and Fast Data Transfer

The ‘Pro’ designation of the camera comes from its internal 256MB DDR3 buffer for quick and stable data transfer and reduced amp glow. The USB3.0 port offers a fast 16 fps capture rate at full resolution with 14-bit ADC and 2.5e read noise.

TEC Sensor Cooling and Anti-Dew Heater

The two-stage TEC cooling system brings the sensor temperature down to 35oC below ambient to keep sensor noise as low as possible, even on warm nights. The heat generated by the TEC is used to counteract the formation of dew on the front window of the camera. The camera’s TEC cooler requires 12V@3A provided with an external power supply (not included). If the camera is powered with a USB2.0 host, the external 12V power supply is also required. When it’s cooled to -20℃, the current noise can be as low as 0.0022e/s/pix, almost negligible.

Please note that the camera needs to be connected to an external 12v power supply to implement the cooling function. We recommend you use 12V@3A DC adapter (5.5*2.1mm, center pole positive) or lithium battery with 11-15V to power the camera.

The camera’s sensor chamber is sealed by four screws in a design that’s extensively tested and very stable. Even when used in higher humidity environments, ASI294MM Pro still operates without dew problems. In addition, ASI294MM Pro has a polyimide anti-dew heater completely fitting the protective window that helps further avoid dew problems. The anti-dew heater power is around 5W and can be turn off in software to save power.

Superb Low-Noise Performance

The ASI294MM camera has a dynamic range of 9 to 13 stops depending on the camera gain settings. The read noise can be adjusted from 1.2e to 7.3e; at a gain of 120dB, you get 13 stops of dynamic range with a read noise of just 1.3e.

This TEC-cooled camera works well for capturing images of deep-sky objects. It also excels as a solar/lunar/planetary camera, especially with telescopes of focal length longer than about 1200mm. The USB3.0 interface and fast capture rate of the camera lets you grab 11MB video at 19fps (in 10-bit ADC high-speed mode) and 16fps (in 14-bit ADC normal mode).

USB3.0 Data Ports and USB2.0 Hub

The camera’s electronics, other than the cooler, are fully powered through the USB3.0 port. The TEC cooler requires 12V@3A provided with an external power supply (not included).

The ASI294MM-Pro also incorporates a USB2.0 hub for powering accessories such as a guide camera and electronic focuser.

The camera has a diameter of 78mm and weighs 410 grams (14.5 oz). It comes with a padded carrying bag, M42-M48 adapter, M54-M48 21mm extender and M48-M48 16.5mm extender, 2” cover, USB3.0 and USB2.0 cables, and a quick-start guide.

Specifications

• Sensor: SONY IMX492 CMOS Back-Illuminated Sensor
• Diagonal: 23.2mm
• Resolution: 11.3 Megapixels 4144X2822 in Bin2 mode (Switchable to 47 Megapixels in Bin1 mode)
• Pixel Size: 4.63µm in Bin2 mode, 2.3µm in Bin1 mode
• Shutter: Rolling shutter
• Exposure Range: 32µs-2000s
• ROI: Supported
• Read Noise: 1.2e @39db gain
• QE peak: TBD
• Full well: 63.7ke in Bin2 mode, 14ke in Bin1 mode
• ADC: 14bit in Bin2 mode, 12bit in Bin1 mode
• DDRIII Buffer: 256MB
• Interface: USB3.0/USB2.0
• Adaptor: M42X0.75
• Protect window: AR window
• Dimensions: 78mm Diameter
• Weight: TBA
• Back Focus Distance: 6.5mm
• Cooling: Regulated Two Stage TEC
• Delta T: 35°C below ambient
• Camera Power consumption: 650mA at 5V
• Cooler Power consumption: 12V at 3A Max
• Working Temperature: -5°C—45°C
• Storage Temperature: -20°C—60°C
• Working Relative Humidity: 20%—80%
• Storage Relative Humidity: 20%—95%

What's in the Box:

• Camera bag
• Camera body
• 2m USB 3.0 Cable
• Quick Guide
• T2 21mm Extender
• T2-M48 16.5mm Extender
• 1.25" Nosepiece
• 1.25" Cover
• M42-M48 Adapter
• 2x 0.5m USB 2.0 Cable
• T2-1.25" Adapter
• 2x Spacer