In two decades, much has changed beyond recognition. Sensors are now back-illuminated CMOS with native 16-bit digitisation. QE is an amazing 90% and readout is a speedy 120 million pixels per second over USB3, a performance that once was unimaginable. What is maintained by QSI’s newest cameras is the integrated design, attention to detail, and bulletproof reliability.
In the design of the 700 series we have taken our best technology. Filterwheels are mechanically indexed to ensure the most precise location for perfect flat fields. The fused silica window is dew resistant and is coated on both sides with high transmission anti-reflective coating to minimise halos. The cameras use a highly efficient 2-stage Peltier cooler that draws less current and delivers more cooling than some other cameras.
The QSI 760 is our flagship product. The full frame IMX455 is widely regarded as the premium sensor for astronomers. The integrated 2”/50mm filter wheel minimises back focus, essential for the widest compatibility with focal reducers. Cable clutter is reduced thanks to the integrated filter wheel, 2 USB2 in sockets and power out. Power sockets have threaded connections for maximum reliability.
| Image Sensor | Sony IMX455 mono CMOS sensor | Sony IMX571 mono CMOS sensor |
| Resolution | 9576 × 6380 | 6244 × 4168 |
| Pixel Pitch | 3.76 um | 3.76 um |
| Sensor Size | 43.3mm diagonal (36mm x 24mm) | 28.3mm diagonal |
| Full Well | 51,000 e- | 51,000 e- |
| Read Noise | 1.2 e- | 1.7 e- (typical) |
| Set Point Cooling at ambient of 20 C | -25 °C | -25°C |
| Frame Rate | 2 FPS (Full Frame image) | 4FPS (Full Frame image) |
| Mount Type | M54 × 0.75 | M54 × 0.75 |
| ADC | 16 bit | 16 bit |
| Backfocus Distance | 31 mm | 31 mm |
| Reading Mode | Rolling shutter | Rolling shutter |
| Exposure Range | 1 ms - 24 hours | 1 ms - 24 hours |
| Dark Current | 0.005 e-/p/s | 0.0008 e-/p/s |
| Filter Wheel Mechanical indexing for reproducible flats | Filterwheel for 2" or unmounted filters, 5 or 7 position | 50mm/ 36mm filters |
| Accessories | Off-Axis guide unit | Off-Axis guide unit |
| Computer System | Windows 10+ Linux USB 3.0 8GB | Windows 10+ Linux USB 3.0 8GB |
| Requirements | Ram 64 bit Operating System. | Ram 64 bit Operating System |