ASI676MC CMOS color camera ZWO

The camera ZWO ASI676MC is equipped with a 12.6 megapixel color CMOS sensor (3552 x 3552 px), 10 mm diagonal and square format. At full resolution, maximum frame rate is 31.2 fps with a 12-bit dynamic range. Equipped with the latest technologies of Sony's STARVIS 2 sensor architecture, the camera offers state-of-the-art functionality: total absence of electroluminescence, wide dynamic range, very high sensitivity in the near infrared and dark current and very low readout noise.

Main features of the camera ZWO ASI676MC

With its 1/1.6" color sensor, the camera can be ZWO ASI676MC is ideal for all-sky weather monitoring and meteor detection. It can also be used for planetary, lunar and solar imaging, or as a self-guided camera. You can take superb color photographs of the planets while avoiding the vagaries of atmospheric turbulence. Thanks to its sensitivity in low light conditions, the 662MC delivers excellent results in visual aided or in deep sky images using the technique "lucky imaging"(fast burst acquisition and subsequent stacking of a large number of deep sky images).

The IMX676 has square pixels only 2 µm on a side. With such small pixels, it is very important to calculate the sampling resulting from your setup according to your observation conditions and your seeing. If necessary, you should adapt the focal length of the instrument or perform binning, so as not to oversample the images too much.

Sensor performance

Designed by Sony for surveillance and security applications, the IMX676 sensor is built on the STARVIS 2 technical architecture. It incorporates powerful functions that produce bright, high-contrast images with high dynamic range, even in extremely limited lighting conditions. The most important of these is the use of an optoelectronic structure known as the "backlit"(or BSI, Backside Illumination sensor). All the sensor electronics are placed below the photosites, which reduces the distance light has to travel through the sensor and the blocking of photons by the non-photosensitive electronics. Sensitivity is greatly increased, even in very low light conditions. The sensor is also extremely efficient in the near infrared (NIR), a spectral band favored by planetary astrophotographers for its reduced sensitivity to atmospheric turbulence. This staggered structure allows more electronics, such as ADCs, to be placed on the sensor itself, minimizing artifacts and noise.

Dark current of an ASI676MC camera as a function of temperature. Dark current is expressed in electrons per second per pixel.

Quantum efficiency and readout noise are the two most important parameters for measuring the performance of a camera. A high quantum efficiency and a low read noise are necessary conditions for a significant improvement of the signal-to-noise ratio.

Relative quantum expansion of the ASI676MC color camera sensor as a function of wavelength

Read noise is the sum of several components: the thermal noise of the photosites, the noise linked to the sensor electronics and the quantization noise of the analog/digital conversion stages. The lower the readout noise, the better the results; therefore, technological work is carried out at all levels to reduce it as much as possible. At the output, the camera incorporates a HCG (High Conversion Gain) device that reduces read noise at high gain while maintaining the high dynamic range that would be obtained at low gain. This HCG mode is automatically activated as soon as the gain reaches 180.

Pixel capacity (FWC), gain, dynamic range and camera readout noise ZWO ASI676MC

Assembly mechanics

The ASI676MC has an M42 female input thread; the rear focus is 12.5 mm. A mechanical M42 to 31.75 mm male converter is supplied, along with a 2 m USB cable and an ST4 autoguider cable. ZWO also offers a well-made 2.5 mm focal length lens. Thus equipped, the camera can also be used as an All-Sky camera for sky surveillance.

Software

As with all cameras ZWO, the main and most complete camera control software is ASIStudio, free downloadable from the manufacturer's web site ZWO. The brand also offers a free SDK (Software Development Kit) to make many free or paid software packages natively compatible with the cameras ZWOPrism, NINA, FireCapture, MaximDL, SharpCap, PHD2, AllSkEye, etc. We invite you to consult the specific documentation of these softwares to know their level of compatibility or to visit the web site of ZWO for a comprehensive list.

ZWO also offers a unified ASCOM controller to control all your accessories through the ASCOM/Alpaca platform. This driver can be downloaded free of charge from the website of ZWO.

For Linux and Mac users, the indi or Indigo controllers are free of charge and are available on the websites of these platforms. Control is done through KStars/Ekos software (for Linux) and AstroImager/AstroTelescope from CloudMakers (for Mac).

Finally, the cameras can be accessed ZWO through video drivers such as DirectShow or TWAIN. For more details, please visit the ZWO.

Electronic features

Mechanical characteristics

Camera dimensions and measurements ZWO ASI676MC

Components supplied

• 1x color camera ZWO ASI676MC
• 1x CCTV fisheye lens 2.5 mm
• 1x USB3 cable (2m)
• 1x ST4 autoguider cable
• 1x adapter M42x0.75 male to 31.75mm male, with socket