QHYCCD QHY5III200M Mono

SC2210 BSI Sensor: 4µm Pixels and High NIR Sensitivity

At the core of the QHY5III200M is the SC2210 back-illuminated sensor, which offers significant sensitivity advantages, especially in the near-infrared. The 4µm pixels provide a large surface area for light collection, boosting signal-to-noise ratio on faint targets and guide stars. This pixel size is an excellent match for the focal lengths of many off-axis guiders and guide scopes, providing accurate tracking without needing a Barlow or reducer to achieve proper image scale.

• Back-Illuminated Structure (BSI): Maximizes photon capture by placing the sensor's wiring layer behind the photodiodes, increasing quantum efficiency.
• Included IR850nm Filter: The camera's high NIR sensitivity can be leveraged for methane band imaging of Jupiter and Saturn, and this filter allows you to isolate that specific wavelength.
• Low Read Noise (0.75e-): The extremely low minimum read noise ensures that faint guide stars are cleanly detected and that planetary detail is not lost in the noise floor during short exposures.

High-Speed Planetary Imaging: 96.5 FPS with a 512MB DDR3 Buffer

For planetary imaging, capturing thousands of frames in a short period is key to freezing atmospheric turbulence. The QHY5III200M is built for this task, streaming full-resolution 1920x1080 frames at 96.5 FPS in 8-bit mode or 60 FPS in 16-bit mode for greater bit depth. The integrated 512MB DDR3 buffer is critical, preventing data bottlenecks and lost frames that can occur when a computer's resources are momentarily strained.

A Dual-Role Guider: 4µm Pixels and 8mm/17mm Back Focus

Engineered as both a planetary imager and a dedicated autoguider, the QHY5III200M features the necessary connectivity and form factor for any setup. A standard ST-4 guide port provides direct communication with your mount, while the lightweight 90g body adds minimal load to your focuser. The camera provides two native back focus distances—8mm and 17mm—to accommodate different optical configurations without requiring a large stack of adapters.

• 8mm Back Focus: Ideal for attaching C/CS-mount lenses directly or for use in setups where minimal back focus is required.
• 17mm Back Focus: Provides the standard spacing needed to insert accessories like a filter wheel or work within the optical path of most off-axis guiders.
• 1.25-inch Format: The camera body slips directly into any standard 1.25-inch focuser or visual back, making it universally compatible.

QHY5III200M vs. ZWO ASI290MM Mini: Pixel Size and Guiding

A common alternative for guiding and planetary imaging is the ZWO ASI290MM Mini. While both are excellent cameras, they are optimized for slightly different scenarios.

• ZWO ASI290MM Mini Advantage: The ASI290MM uses smaller 2.9µm pixels. This can yield higher resolution on shorter focal length telescopes, resolving finer detail if the seeing conditions permit.
• QHY5III200M Advantage: The larger 4µm pixels of the QHY5III200M are more sensitive and provide a better image scale for guiding on longer focal length instruments (like SCTs with off-axis guiders) without resorting to binning. This can result in detecting more guide stars and achieving a higher signal-to-noise ratio on each one, leading to more stable guiding.