ZWO ASI662MM Mono

Sony IMX662 Sensor: 91% QE and 38.2ke Full Well

The core of the ASI662MM is its back-illuminated Sony sensor, which achieves a 91% peak QE, making it extraordinarily sensitive to faint light. This monochrome design utilizes every photon hitting its 1920 x 1080 pixel array. The sensor's 38.2ke full well capacity is nearly three times larger than previous generations, allowing you to capture extreme brightness variations—from Jupiter's equatorial bands to its dimmer polar regions—in a single exposure without clipping highlights.

Zero Amp Glow & 256MB DDR3 Buffer

ZWO engineered the ASI662MM with a circuit design that produces zero amplifier glow, a common source of noise in uncooled CMOS cameras. This eliminates the need for dark frame subtraction to remove corner glow, simplifying your image processing workflow. To handle the data from its high-speed 107.6 FPS capture rate, a 256MB DDR3 buffer provides a stable, high-speed data cache that prevents dropped frames and ensures consistent transfer to your computer.

ASI662MM vs. ASI462MM: A Generational Leap in Planetary Imaging

While the ASI462MM remains an excellent camera known for its infrared sensitivity, the ASI662MM represents a significant step forward for imaging in the visible spectrum. The primary advantage of the ASI462MM is its response deep into the IR, which can be beneficial for cutting through atmospheric turbulence when imaging planets with a methane filter. However, for standard LRGB planetary work, the ASI662MM's specifications are superior across the board.

• Full Well Capacity: The ASI662MM's 38.2ke full well is dramatically larger than the 13ke of the ASI462MM. This gives you far greater dynamic range, preventing the bright cores of planets and lunar features from blowing out while still capturing subtle albedo details.
• Read Noise: At 0.8e, the ASI662MM's read noise is lower, resulting in a cleaner signal-to-noise ratio, especially during short exposures used in lucky imaging.
• Amp Glow: The ASI662MM has zero amplifier glow, a persistent artifact on the ASI462MM that requires calibration frames to remove.

Uncooled Design for High-Speed Imaging and Guiding

The ASI662MM's uncooled design keeps its weight down to just 0.3 lb., making it an ideal choice for planetary imaging where active cooling is unnecessary for short video captures. This high sensitivity and low read noise also make it a capable autoguider. As an uncooled camera, thermal noise will build up on multi-second guide exposures, but for the vast majority of guiding scenarios where exposure times are under 5 seconds, the camera's raw sensitivity delivers sharp, consistent tracking.

Connectivity: 12.5mm Back Focus and Standard Ports

The ASI662MM is built for easy integration into any imaging train. It uses a standard M42 thread for direct connection and includes a 1.25" nosepiece for use in standard focusers or filter wheels. The native back focus of 12.5mm is a critical distance for correct spacing with various accessories.

• USB 3.0 Interface: Provides the 5Gb bandwidth necessary to run the camera at its maximum 107.6 FPS frame rate.
• ST-4 Guide Port: Allows for direct connection to a telescope mount for autoguiding, bypassing the need for pulse guiding via a computer.
• M42x0.75 Threads: The standard T-thread interface ensures compatibility with a vast ecosystem of adapters, filter wheels, and off-axis guiders.