SWIR DSO Cooled Camera ASI991MM Pro

ASI991MM Pro adopts 1/4" Sony-IMX991InGaAs sensor, featuring a wide band from 0.4um to 1.7um. It is the first and most powerful SWIR camera that ZWO offers. The camera has a large full well capacity, high sensitivity with an incredible QE peak value of 80% at 1200nm and a big pixel size of 5um.

The great performance in capturing short wave infrared lights makes it applicable for SWIR imaging, photometric measurement, optical communication, laser and optical laboratory, and more!

NOTE: External power supplies are needed for all ASI cooled cameras. It is recommended to use a 12V @ 3A DC adapter (5.5 x 2.1mm, center pole positive) or a lithium battery with 11-15V to power the camera. Be aware that using any power supply with this voltage range can lead to irreparable damage to the camera.

Penetrates Through Clouds and Fog and Captures Stars in the Daytime

ASI991MM Pro can capture high definition images. the wide band (0.4-1.7um) gets the camera's sensitivity into a higher level making it capable of capturing beautiful night skies in thin clouds. Also, allows you to photograph stars during the daytime.

No Amp Glow

Traditional CMOS sensors produce a weak infrared light source during operation, which is often seen in the corner of uncalibrated images. This is the tell-tale sign of "amp glow". You won't have to worry about amp glow when using high gain, long exposure imaging when using the ASI991MM Pro.

Camera Curve: Readout Noise

Readout noise is generated in the amplifier on the chip that converts the stored charge of each photodiode (i.e., pixel) into an analog voltage to be quantified by A/D conversion.

The lower the readout noise is, the better the image SNR you'll get. Compared to traditional CCD SWIR cameras, the ASI991MM Pro keeps it's readout noise at a very low level.

Quantum Efficiency

QE curve and readout noise are two of the most important elements to measure a camera's performance. Based on ZWO's calculation, the QE peak value of the ASI991 is over 80% at 1200nm.

Two-Stage TEC Cooling

The TEC cooling system can precisely control the temperature of the sensor, and lower it to 30-35 degrees Celsius below ambient temperature.

It is recommended to use the camera at low temperatures for better imaging performance.

*The Delta T 30-35 degrees Celsius is tested at 30 degrees Celsius ambient temperature. It might get down when the cooling system is working for a long time. Also, as the ambient temperature falls, the Delta T would also decrease.

Connection Method

• 1. M43-T2 adapter ring
• 2. EOS-T2 adapter ring
• 3. 2" filter (optional)
• 4. 1.25" nosepiece
• 5. 1.25" filter (optional)
• 6. T2-1.25" adapter (optional)
• 7. T2 11mm ring
• 8. T2-M48 16.5mm extender
• 9. T2-T2 adapter ring
• 10. 1.25" / 36mm / 31mm EFW
• 11. EOS-EFW adapter ring

Connection to External Device

Structural Dimension Diagram

• No amp glow
• Capture stars during the day
• Quantum efficiency
• Two-stage TEC cooling