About this product
Model: zwo_asi294mc-pro
Part Number: ASI294MC-PRO
The first astronomy camera series equipped with SONY's new IMX294CJK sensor.
The ZWO ASI1294MC features Sony's remarkable IMG294CJK 4/3 CMOS sensor with a massive 4144x2822 resolution! That's over 11 megapixels!
FEATURES
- Sony IMX294 4/3 CMOS Sensor
- Extremely low read noise - 1.2e @30db gain
- 14Bit ADC - provides real 14bit dynamic range
- Electronic shutter - no issues with vibrations sometimes found in mechanical shutters
- USB3.0 Port (back compatible with USB2.0) - 16fps@4144×2822
- AR-coated protective window - all light can pass
- Compatible with Windows / Mac OS / Linux
IMX294 Sensor
23.2mm diagonal, approximately 11.7 megapixels.
Back-illuminated highly sensitive 4.63μm pixels.
The 'IMX294CJK' is the first image sensor for astronomy cameras to adopt the 4/3 format and achieves the number of pixels required for 4K at 120 frame/s (in ADC 10-bit output mode, ASI294MC can run up to 25fps at 4k format based on USB3.0 bandwidth). In addition, the large-size pixels achieve SNR1s of 0.14 lx*, which is very close to ZWO's ASI224 (0.13 lx*).
DDR Memory Buffer
ZWO Pro cameras feature a 256MB DDR3 memory buffer to help maintain data transfer stability and reduce amp-glow issues caused by the slower data transfer speed when using a USB 2.0 port.
All ZWO cameras include a 2-year warranty.
Camera Field of View Simulator
Astrophotography Performance
Exceptional low-illumination performance of SNR1s: 0.14 lx is achieved using a large-size optical system and by expanding the area per pixel to 4.63 µm. This makes the IMX294CJK sensor an excellent choice for astrophotography which requires high performance in low light.
14bit ADC & 13 stops DR
14bit ADC can achieve 13 stops dynamic range, which is even better than ASI1600.
HCG Mode
HCG mode will be on when the gain is higher than 120 (12db), and read noise will drop below 2e but in the same dynamic range (13 stops).

Full well Capacity
63700e full well is three times greater than the ASI1600’s capacity. Even bright stars won’t saturate under long exposure.
A higher SNR (signal-to-noise ratio) can be achieved with just one exposure.
Reliable Mechanics
ZWO's ASI294MC Pro has the same mechanics as their highly regarded ASI1600 Pro. Four screws seal the sensor chamber.
Even when used in higher humidity, the ASI294MC Pro will work fine without dew problems.

High QE
The IMX294 sensor is a BSI (back-illuminated type) sensor, so it has a very high QE (ZWO measure the QE peak higher than 75%).

Dark Current
The dark current of the ASI294 is slightly higher than the ASI1600, based on ZWO test results.
Dark frame sample @ Highest dynamic range settings, 300s, -10°C, bin1.
ASI294MC Pro Dark Frame

USB Ports
USB 3.0 Port: Provides 5Gb bandwidth, making it possible for the ASI294 Pro to run at 16 fps (14bit, normal mode) or 19 fps (10bit, high-speed mode) at full resolution (11.7Mega).
Recommended cooler power supply: 12V @ 3-5A (or more) DC adapter (2.1×5.5mm, centre pole positive). Also suitable: DC battery with 9-15V.
Using a battery with 9-15V is also suitable for the cooler power supply.
USB 2.0 HUB: Connect with various accessories, such as filter wheel, guide camera and electronic focuser, for easier cable management. The USB Hub draws power from an external power supply if you have one connected. Two short 0.5m USB 2.0 cables are included.

Cooling System
The ASI294 Pro has a 2-stage TEC cooling system that enables deep cooling (35°C-40°C below ambient). The cooler requires an external power supply - which is not included with the camera.
ASI294MC Connection Drawing

- M43-T2 adapter (optional)
- EOS-T2 adapter (optional)
- 2” Filter (optional)
- 1.25” T-Mount
- 1.25” Filter (optional)
- M42-1.25” adapter
- T2 extender 11mm
ASI294MC Mechanical Drawing

What's in the box
- ASI294MC-Pro Camera
- Soft Padded Case
- T2-1.25" Nosepiece Adapter
- 1.25" Cap
- 2-metre USB 3.0 Cable
- USB 2.0 Short Cable x2
- T2-1.25" Adapter
- T2 Extender 21mm
- T2-M48 16.5mm Extender
- Spacers x2
- Quick Start Guide
- Driver CD
Specifications
Sensor | 4/3″ SONY IMX294 CMOS |
Diagonal | 23.2mm |
Resolution | 11.7Mega Pixels 4144X2822 |
Pixel Size | 4.63µm |
Bayer Pattern | RGGB |
Shutter | Rolling shutter |
Exposure Range | 32µs-2000s |
ROI | Supported |
Read Noise | 1.2e @39db gain |
QE peak | TBD |
Full well | 63.7ke |
ADC | 14bit |
DDRIII Buffer | 256MB |
Interface | USB3.0/USB2.0 |
Adaptor | M42X0.75 |
Protect window | AR window |
Dimensions | 78mm Diameter |
Weight | 410g |
Back Focus Distance | 6.5mm |
Cooling | Regulated Two Stage TEC |
Delta T | 35°C-40°C below ambient |
Camera Power consumption | 650mA at 5V |
Cooler Power consumption | 12V at 3A Max |
Working Temperature | -5°C—45°C |
Storage Temperature | -20°C—60°C |
Working Relative Humidity | 20%—80% |
Storage Relative Humidity | 20%—95% |
Supported Resolutions:
10Bit ADC
14bit ADC
Additional resolutions can be user defined.
Downloads / Manuals
The following manuals and downloads are available for this product:
Software
ZWO Software and Drivers
Customer reviews
Average Rating (15 Reviews): | |
Very pleased with the camera. Just need some clear skies in order to use it. 14 January 2023 | Robert
My camera arrived very quickly and well packaged. Usual FLO excellent service.
As you might expect I have not had a chance to use the camera yet due to the weather! This camera has been well tried and tested and is the reason I myself purchased it but I will update this review once I get to use it.
06 January 2022 | Stuart
Finally - the first few hours of clear weather since I purchased this camera. It is fantastically easy to use especially combined with the ASIAIR Plus, though it is worth spending a bit of time on the forums to get the correct gain settings etc. I would highly recommend this; it is my first dedicated AP camera and produced amazing images of M31 for a complete novice in a light-polluted back garden. This is one of several purchases from FLO recently and I have to say that it is truly the best online shopping experience - the staff give good advice and the shipping is second to none with items arriving when you cannot believe that they have even left the warehouse. I cannot recommend FLO and this camera enough.
17 August 2021 | Paul
I was really apprehensive in making such a large purchase for my hobby that i've been doing for 2 years now, however, I am very glad I took the plunge and bought this excellent camera.
Upgrading from an unmodified, second hand Canon 700D to this was like night and day, don't get me wrong I love my 700D, but the difference in image quality is almost hard to believe without actually seeing it.
I have mine paired up with a 72ED Pro scope and an Astronomik L3 UV/IR filter which helps keep the chromatic aberration of the 72ED's glass well in check.
Using an ASIair, as I have for the past year or so, this camera was literally as simple as plug and play, with limited, easy to understand options in the app and everything working without any issues, it gathers so much light you don't even need to find a bright star to focus, almost any patch of sky will work.
During the summer months cooling has been set to -10c and has never taken more than 5 minutes to reach and has no problem staying there all session long.
I have been taking 4min subs at 120gain -10c and have yet to see ANY noise in my stacked images, I have noticed with those setting that bright stars are starting to become over exposed, which will be easily fixed by taking 2 min exposures instead next time out. At these setting I have also been using 20 darks and 60 bias files to calibrate with and have not seen any hint of amp glow or color blotching or any other artifacts in my stacks or even single frames.
I am absolutely loving this camera and the absolutely huge improvement it has provided over my DSLR.
Brilliant first dedicated astronomy camera 02 July 2021 | David
I have owned the ZWO294 mc pro for about 3 months now, long enough to do a reasonable review, I think. This is my first dedicated cooled astro cam having used a canon DSLR up to this point. The change is initially quite daunting but after few nights most problems get sorted. The biggest change is not having a nice friendly live view. This is however easily overcome when you get the settings right! Gain350 Bin4. A looped exposure of a quarter of a second gives a very good live view simulation and focusing is easy. With five seconds you can usually see the object you are imaging. Set the gain to 120 and your off. The cooling and warning aids in APT make cool down and warm up simple. The amp glow calibrates out completely and easily. Darks are taken in the daytime as the temperature is fixed by the cooler.
The images produced have exceeded expectations in every way. The 4/3 sensor is a great size, has a pleasing aspect ratio, produces great colour and is very sensitive. The resolution is way more than adequate. Even coming from a full frame sensor, the narrower field has never been a problem and can just represent an opportunity to buy another small scope! The pixel scale is good, and it works well with all three scopes I have used it with. These have focal lengths of 435,700, and 1460mm. The 700mm refractor seems particularly tuned in to this sensor. It also works very well with the L-extreme filter.
Overall, I find it hard to imagine finding a better introduction to dedicated camera astrophotography.
ZWO ASI294MC PRO CMOS USB3 Colour Camera 15 June 2021 | Peter
FLO have asked me to review my June 2021 camera purchase but I have only had one brief session under the stars to test it. All seems fine using it with a Skywatcher 200P Newtonian reflector on an HEQ5 mount. I use a Lynx EQDirect connection to my Windows USB2 laptop running AstrophotographyTool and PHD2 guiding. I have been imaging with a modified Canon 450D up to now so it is going to take me quite a while to get used to the 294. For my test I targeted M13 with 180s subs at a gain of 130 and the camera cooled to 0 degC. The result was rather overexposed so maybe 60s or even shorter subs would have worked better. I can’t fault FLO for their service, before submitting my order they responded the same day to my email query regarding spacers needed to get the right back focus for my Baader Coma Corrector (they confirmed all are included with the camera). DHL delivered next day but it was a good job that FLO used a lot of foam and bubble wrap because the camera was fine despite the DHL box being dented, DHL had not given it the best of care.
I think it likely that I will buy from FLO again in the future.
Peter.
28 March 2021 | Gary
I ordered this Friday lunch time, told it would be delivered the following Monday. However it arrived on Saturday at 9am, less than 24hrs, even by FLO's standard that was quick. I set the camera up today and started doing a dark library, from what I can tell at this point the camera performs as expected. Now gotta wait on some clear sky.....
ZWO ASI 294MC-PRO USB 3.0 Cooled Colour Camera 15 February 2021 | John
I received the camera day after ordering, as usual, great service by FLO.
Setting up and using the camera, APT, and Ascom for controlling everything was a big learning curve which went well the first time and produced a nice first light image.
The second time was more complicated due to my inexperience with using a CCD camera. More research on my part would have been sensible.
The cooling assistance in APT didn't seem to work properly giving me error messages saying the temperature selected cannot be reached...this happened a few times but if I started the cooling again it reached the correct temperature.
I put this down to APT not the camera!
I'm going to enjoy this camera now I'm more familiar with how to control things.
08 November 2020 | Tony
After using a standard Canon 70D DSLR connected to a RedCat51, this camera is a step up. Only had a limited chance to use this - moonlit and a lot of light pollution but even so, the images had more colour, less noise. The camera has all the connections I needed to connect the camera to the scope - no mucking about with purchasing additional adapters.
FLO were at their usual best providing quick responses to my newbie questions.
Very happy (apart from the lack of decent weather!)
05 November 2020 | Cedric
I got that camera a few weeks back, thanks to FLO teams and usual speedy delivery.
I finally got a chance to do some imaging session (clear skies). And I have to say, I am really happy, that camera was quite easy to setup (literally just cables to plug and you are running on gas). I was really happy with the quality of the pictures produced even though I was still playing around with the settings. The sensor does a great job and the cooling system is quite effective, it seemed to be a tag slow to get to the requested temperature so I would recommend to start the cooling 10 minutes prior to your imaging session based on how cold you want your sensor.
So far I haven't experienced any issue at all.
Overall I am very happy with it and I would definitely recommend it.
An excellent next step from a DSLR 19 September 2020 | Paul
I had been using an old EOS50D and had been planning to change to a CMOS camera in around 12 months. I was finding the 50D was beginning to hold me back, it has a sensor that's prone to banding and no amount of dither was able to fix it. I also had 11 batteries - all of them bad. This meant I was constantly swapping batteries and recharging through an imaging session. It was time for a change.
When it comes to colour CMOS, the 294 hits a sweet spot in terms of price and performance. Judging by the YouTube and forums it's a popular choice. The camera is light, but very solid. It won't strain your focuser. Finding back focus with the included adapters was easy, once I worked out what thread I needed to end up on (I use 200PDS and the required 55mm takes all the spacers). The supplied cable is a little short, but its flat profile makes for easy routing.
Setup and usage is simple - I use Astrophotography tool and it's a case of plug in, set to cool and you're running. The fan is quiet and won't disturb anyone. There have been a couple of times I forgot to plug in the PSU...
Image wise I have hugely impressed by the results. The camera produces sharp, detailed images, consistently. I've not had issues with gradients or amp glow (there is an issue with a flare on one side of the sensor, with calibration frames it's not an issue. I only know about it because of the web),
My current settings are unity gain, 3 minutes and -10 degrees. My first night of imaging produced an okay version of the Western Veil, the second night produced an M16 that knocked it out of the park. Since then every session has produced solid images, plenty of detail and very little noise. I now have a certainty that I will have good data at the end of the night.
Practically the two USB sockets on the back really help. I run my guide cam into one of them and it reduces trailing cables.
One area I have had to adapt to is the smaller sensor. Some targets can be difficult to fit in with a 900mm focal length scope. In the short term I'll adapt and mosaic larger targets. In the longer term intend to use it with a wider field refractor.
I did initially encounter some issues with bloated stars, but soon realised this was due to heavy handed processing!
At the time of writing we've had a run of around 10 clear nights. The 294 has massively impressed. For me it was definitely the right step at the right time. In some ways it's almost boring in that it just does what you ask of it. Transition for DSLR is easy. Cooling and Warm up will add some additional time to your imaging sessions, but you soon factor that in.
Should you choose this over mono? I struggled with this question, but realised with my workflow, list of targets and time restrictions OSC was the right choice for me. With that in mind the ASI294MC Pro is the right spec at the right price. Although I have been "doing the telescopes" for 30 odd years, I still class myself as an advancing beginner at imaging and I'm certain it will be a long time before I outgrow this camera.
So to sum up. This camera is a significant step up from a DSLR. You will have less noise and capture great detail. If you have been using a DSLR for a while, you won't struggle with the transition, but will need to remember the reduced sensor size. At around £1,000 this is a hefty investment, but it will pay you back immediately.
Read all 15 customer reviews...
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