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ZWO ASI991MM Pro USB3.0 Monochrome SWIR Camera
The ZWO ASI991MM Pro SWIR Camera features a high-sensitivity monochrome sensor, 1280x1024 resolution, USB3.0, and advanced cooling, ideal for capturing detailed near-infrared astronomical and scientific images.
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ZWO's First SWIR Camera - Daytime Astrophotography
The ZWO ASI991MM Pro is a top-tier monochrome SWIR (Short-Wave Infrared) camera, featuring the Sony IMX991lnGaAs sensor. This 1/4" sensor offers an impressive spectral range from 0.4μm to 1.7μm, making it ZWO’s most powerful SWIR camera to date.
This camera excels in high-sensitivity imaging, boasting a peak quantum efficiency (QE) of over 80% at 1200nm and a pixel size of 5μm. This high sensitivity allows the ASI991MM Pro to capture detailed images even through challenging conditions such as clouds, fog, or during daylight.
The ASI991MM Pro incorporates zero amp glow circuitry, effectively eliminating the common issue of infrared light artifacts seen in traditional cameras. This ensures cleaner, more accurate results during long exposure imaging. Additionally, the camera features a low readout noise level, enhancing the signal-to-noise ratio (SNR) and providing superior image quality.
Equipped with a two-stage TEC cooling system, the ASI991MM Pro can maintain the sensor temperature 30°C to 35°C below ambient. This cooling capability is crucial for achieving optimal imaging performance and is particularly effective when used at lower temperatures.
The ZWO ASI991MM Pro is designed for a range of applications, including SWIR imaging, photometric measurements, optical communication, and laser research. Its advanced features and high performance make it a versatile and valuable tool for capturing high-definition images across a broad spectrum.
Full Specifications
| Type | Monochrome |
| Sensor Type | IMX991 |
| Sensor Size | 3.3x2.6mm |
| Pixel Size | 5 μm |
| Read Noise | 21.27e |
| Resolution | 656x520 |
| Max Framerate | 144 FPS |
| Zero Amp Glow? | Yes |
| Delta T | 35°C below ambient |
| Memory Buffer | 256MB DDR3 |
| Shutter | Rolling Shutter |
| QE Peak | 80% |
| Full Well | 127,000e |
| Back Focus | 6.5mm |
| ADC | 12-bit |
| Exposure Range | 0.4μm - 1.7μm |
| USB | 3.0 |
| Adapter | M42 X 0.75 |
| Weight | 700 g |
Recommended Accessories
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ZWO 12V 5A Power Adapter for Cooled Cameras Used to power your compatible ZWO cooled camera or electronic device. |
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ZWO Desiccant Tablets for Cooled Cameras Replace used dessicant tablets as required with the ZWO Dessicant Tablets for Cooled Cameras to keep your cooled camera functioning optimally. |
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M42 T-Thread Spacer Ring Kit Add a M42-T-Thread Spacer Ring Kit to adjust backfocus spacing as required. Comes with 4 convenient sizes. |
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ZWO 12V 5A Power Adapter for Cooled Cameras Used to power your compatible ZWO cooled camera or electronic device. |
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ZWO Desiccant Tablets for Cooled Cameras Replace used dessicant tablets as required with the ZWO Dessicant Tablets for Cooled Cameras to keep your cooled camera functioning optimally. |
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M42 T-Thread Spacer Ring Kit Add a M42-T-Thread Spacer Ring Kit to adjust backfocus spacing as required. Comes with 4 convenient sizes. |
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About ZWO Optical: Astrophotography has never been easier
Established in 2011, ZWO Optical is a fast-growing global astroimaging camera powerhouse based in Suzhou China. They focus on building and innovating groundbreaking CMOS cameras such as the iconic ZWO ASI120MM Monochrome CMOS camera (the first-ever planetary CMOS camera to beat a CCD in the early 2010s). ZWO continues to pioneer new astrophotography technology with revolutionary features to capture exceptional quality of images of space that will last you a lifetime.
Today, ZWO cameras are recognised by every passionate astrophotographer and are available in over 25 countries internationally.
Product Code: ASI991MM-P