ZWO ASI294MC Pro Color
- 11.7 Megapixel 4/3" Sony IMX294 Color CMOS Sensor
- 4.63µm Pixel Size
- Massive 63.7ke- Full Well Capacity
- Extremely Low 1.2e- Minimum Read Noise
- Two-Stage TEC Cooling with Sealed Sensor Chamber
- 256MB DDR3 Onboard Image Buffer
See exactly how your targets fit with the ZWO ASI294MC Pro Color, on real sky survey data.
Launch Imaging AssistantCheck which filter and adapter sizes clear the sensor with the ZWO ASI294MC Pro Color, and how much light the corners lose.
Check vignettingThe ZWO ASI294MC Pro combines a high-resolution 11.7 MP Sony back-illuminated sensor with large 4.63µm pixels on a 4/3" format chip. Its massive 63.7ke- full well capacity and exceptionally low 1.2e- read noise capture extreme dynamic range in a single exposure, from faint nebulosity to bright stellar cores. The integrated 256MB DDR3 buffer ensures stable, drop-free data transfer over USB 3.0 at a full resolution frame rate of 16 fps with its 14-bit ADC.
The heart of the ASI294MC Pro is its 23.2mm diagonal Sony IMX294 sensor, a proven performer for deep-sky imaging. The back-illuminated (BSI) architecture maximizes photon collection, while the large 4.63µm pixels are well-suited to a wide range of refractors and reflectors. Its greatest asset is the 63.7ke- full well depth, which allows you to take longer sub-exposures on targets with bright stars, like the Orion Nebula (M42) or the Hercules Cluster (M13), without saturating the stars and losing color information.
Deep-sky astrophotography requires long exposures, where thermal noise from the sensor can degrade image quality. The ASI294MC Pro's two-stage TEC cooling system dramatically lowers sensor temperature, resulting in clean, low-noise images. The sealed sensor chamber lets the camera work well without dew problems, even in higher humidity environments. For data stability, the 256MB DDR3 memory buffer acts as a high-speed cache, preventing dropped frames that can occur with slower computers or heavy USB traffic, a critical feature when capturing hundreds of exposures for a final image.
While the ASI533MC Pro offers the benefit of zero amp glow, the ASI294MC Pro provides a significantly larger imaging canvas. The choice depends on your primary targets and telescope.
The camera body features a standard female M42x0.75 thread for direct connection to your telescope's focuser or accessories. With a native back focus of only 6.5mm, you can easily integrate filter wheels, filter drawers, and off-axis guiders into your imaging train. With the 11mm T2 extender attached (17.5mm back focus), the included T2-M48 16.5mm and 21mm extenders help you achieve the standard 55mm back focus distance out of the box. A built-in USB 3.0 port provides high-speed image download, while two additional USB 2.0 ports act as a powered hub, letting you connect your guide camera and electronic focuser directly to the ASI294MC Pro to simplify cable management.
The primary advantage is its large, rectangular field of view. With a 23.2mm diagonal, the 4/3" sensor is ideal for capturing expansive deep-sky objects like the North American Nebula (NGC 7000) or the Veil Nebula complex without needing to create a mosaic. This format is a significant step up from smaller 1-inch or 1/1.8-inch class sensors.
An 80mm refractor with a focal length of around 400mm is an excellent match for the ASI294MC Pro. At 400mm the sensor covers about 2.7 x 1.9 degrees (about 3.3 degrees on the diagonal), enough to frame the main disc of the Andromeda Galaxy (M31) with satellite galaxies M32 and M110 in a single shot. Longer focal lengths, up to 600mm, will need a 2-panel mosaic for the whole galaxy.
Yes, like many CMOS sensors of its generation, the ASI294MC Pro can exhibit some amp glow on very long exposures. However, this is a predictable pattern that is easily and completely removed during post-processing by subtracting properly matched dark frames, a standard part of any deep-sky imaging workflow.
At the native f/10 focal ratio of a typical 8" SCT (~2000mm focal length), the 4.63µm pixels would result in significant oversampling. To achieve a better image scale, you should use a focal reducer (typically 0.7x or 0.63x) with the SCT. This brings the focal ratio down to f/7 or f/6.3, making it a much better pairing for the ASI294MC Pro's pixel size and providing a wider field of view.
The two-stage TEC cooler requires an external power source. The camera's power input is rated for 12V @ 3A Max. A stable, regulated 12V DC power supply with at least 3A, and preferably 5A, is recommended. Current ZWO cooled cameras no longer run from USB power alone, so the camera will not operate without this 12V supply.
The ASI294MC Pro (Color) is for simplicity and efficiency. You can capture a full-color image in a single set of exposures, making it ideal for those with limited imaging time or who prefer a simpler workflow. The ASI294MM Pro (Monochrome) offers higher ultimate resolution and sensitivity, especially for narrowband imaging, but requires a filter wheel and at least three times the imaging time (for LRGB) to produce a color image.
| SKU | ZWO-ASI294MC-P |
| Camera Series | ZWO ASI294 |
| Sensor | Sony IMX294 4/3" Back-Illuminated Color CMOS |
| Resolution | 4144 x 2822 (11.7 MP) |
| Pixel Size | 4.63 µm |
| Sensor Dimensions | 19.1mm x 13.0mm (23.2mm diagonal) |
| Cooling | Cooled, Two-Stage TEC |
| Anti-Dew Heater | No (sealed sensor chamber) |
| Image Buffer | 256MB DDR3 Memory |
| Bit Depth | 14-Bit |
| Max Frame Rate | 16 fps at 4144x2822 (14-bit) / 19 fps at 4144x2822 (12-bit) |
| Full Well Capacity | 63.7ke- |
| Read Noise | 1.2e- to 7.3e- |
| Shutter Type | Electronic Rolling Shutter |
| Exposure Range | 32 µs to 2000 s |
| ROI Support | Yes |
| Back Focus | 6.5mm |
| Telescope Interface | M42 x 0.75 |
| Computer Interface | USB 3.0 / USB 2.0 |
| Power Requirements | 12V @ 3A Max, external supply required (camera does not run from USB alone) |
| Weight | 0.90 lb |
| Operating Temperature | -5°C to 45°C |
| Storage Temperature | -20°C to 60°C |
| Operating Humidity | 20% to 80% |
| OS Compatibility | Mac, Windows, Linux |
| Cooling delta T | 35°C below ambient |
| Peak QE | 75% |
| Color or Mono | Color |
ASI294MC Pro Cooled Color Camera
× 1
T2 Extender (11mm, pre-installed)
× 1
Soft Padded Camera Bag
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USB 3.0 Cable (6.5 ft)
× 1
USB 2.0 Cable (1.6 ft)
× 2
T2 Extender (21mm)
× 1
T2-M48 Extender (16.5mm)
× 1
M42-M48 Adapter Ring
× 1
T2-1.25" Filter Adapter
× 1
1.25" Nosepiece
× 1
Spacer Rings
× 4
2" Dust Cap
× 1
Quick Guide
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