ZWO ASI991MM Pro Cooled Camera

The ZWO ASI991MM Pro is an advanced monochrome astrophotography camera built to deliver outstanding deep-sky imaging performance with exceptional sensitivity, low noise, and high quantum efficiency. Whether you're an experienced astrophotographer pushing the limits of deep-space object imaging or a scientific researcher needing precision data, this cutting-edge CMOS camera is designed to exceed expectations.

High-Performance Sony Sensor for Stunning Details

At the heart of the ASI991MM Pro is the Sony IMX991 back-illuminated sensor, engineered to maximize light collection and reduce noise. With an ultra-sensitive 1.3-megapixel resolution (1280 x 1024) and an impressive quantum efficiency (QE) of over 90%, this camera captures faint details in galaxies, nebulae, and other celestial objects with remarkable clarity. The back-illuminated design significantly enhances photon capture, making it a top choice for imaging in challenging low-light conditions.

Ultra-Low Read Noise for Unparalleled Image Quality

The ASI991MM Pro offers read noise as low as 0.6e, allowing for exceptionally clean and high-contrast images even at short exposures. This ultra-low noise capability ensures better signal detection and improved stacking efficiency, critical for capturing high-dynamic-range details in deep-space imaging. With a 14-bit analog-to-digital converter (ADC), it provides excellent grayscale depth, preserving fine details and subtle variations in brightness.

Advanced Cooling System for Maximum Stability

Equipped with a two-stage TEC cooling system, the ASI991MM Pro achieves cooling down to -35°C below ambient temperature. This dramatically reduces dark current noise, resulting in cleaner images with improved signal-to-noise ratios. The cooling system is optimized for long-exposure astrophotography, ensuring consistent performance across multiple imaging sessions. The efficient heat dissipation design prevents sensor overheating, maintaining a stable imaging environment even in warm conditions.

Fast Data Transfer with USB 3.0 & DDR3 Buffer

The high-speed USB 3.0 interface allows for rapid data transfer rates, minimizing download times even with high-resolution, long-exposure images. Additionally, the 256MB DDR3 buffer ensures smooth data handling and prevents frame loss, making it ideal for high-speed planetary imaging as well as deep-space astrophotography. The camera supports real-time preview and quick frame captures, providing astrophotographers with an efficient workflow.

Optimized for Narrowband and LRGB Imaging

For astrophotographers specializing in narrowband imaging, the ASI991MM Pro’s high QE and minimal amp glow make it a perfect companion for H-alpha, OIII, and SII filters. The deep well depth of 40,000e- ensures that even the brightest stars retain detail without overexposure, while maintaining excellent sensitivity to faint nebulosity. The smooth tonal transitions and high dynamic range make it equally effective for LRGB color imaging when paired with a filter wheel.

Robust Build Quality and Compatibility

• USB 3.0 and ST4 Guide Port provide seamless connection to guiding setups for precise autoguiding.

• Compact and lightweight design, weighing approximately 500g, balances well on a wide range of telescope setups.

• Broad software compatibility, working with major astrophotography platforms including ASIStudio, FireCapture, SharpCap, NINA, and more.

• Standard M42 and 1.25” nosepiece adapters allow easy integration into existing astrophotography setups, ensuring flexibility in different imaging rigs.

ZWO has all their information available for download on their website in a perfectly laid out section. Check it out here for software and drivers and here for manuals and guides.

One of the coolest gadgets, and a neccessity according to a majority of ZWO users, is the ASIair Pro.  It is an all-in-one wireless camera solution.  The ASIair pro gives you control of focus, image taking, plate solving, and computerized mount control with the included SkySafari bridge all controlled by your smartdevice or tablet.  It really is pretty awesome.