Review of the ZWO ASIAIR Plus

M17, the Omega Nebula: Imaged using an ASIAIR Plus, ASI2600MM, Skywatcher Quattro 250P and Saxon AZEQ6.

The ASIAIR Plus: A Boon for Astrophotography and ElectronicallyAssisted Astronomy(EAA)

ZWO ASIAIR Plus Integrated Astrophotography Controller MSRP $299 from ZWO direct

In years past, entering the world of astrophotography would have entailed overcoming daunting technical hurdles. Mount control, camera control. Autoguiding, various applications, and getting it all to work together. This usually involved either a laptop next to the mount or a mini-PC on the mount that ran Windows with a tangle of cables and connectors running from the computer to the various devices like camera, guide cam, focuser and mount. To top it off, the budding astrophotographer would be expected to learn multiple applications such as PHD2(auto guiding, some kind of planetarium software, and the imaging and scope control itself, typically Sequence Generator Pro, NINA, APT etc.

Enter the ASIAIR Plus. It is a fully integrated controller coupled with an elegant, user-friendly UI that runs on a smartphone or tablet giving the user easy access to most of the necessary controls needed for a complete astrophotography setup. It combines the functions of a controller as well as a power distributor at a fraction of the cost and weight of a NUC + Powerbox.

Fig 1. ASIAIR Plus and NUC + Powerbox size comparison

Fig 2. Cable managememt

For me the simplicity and user-friendliness of the UI is a lifesaver. It combines all of the main functions of astrophotography in a single screen.

The icons across the top are from left to right: Wifi/Connection, Main Camera, Guide Camera, Mount, Electronic Filter Wheel, Electronic Autofocuser, Storage and Status.

Fig.4 ASIair app main screen

Functions currently supported by the ASIair Plus include an Autorun and Plan mode that can be used to schedule deep sky object imaging including multiple targets, live stacking mode which can be useful for EAA(electronically assisted astronomy), and a video mode for planetary lucky imaging,

In addition to the astrophotography functions, it is also a power distribution box. The status screen provides real-time information on the input and output power on each of the four 12v DC outputs. Crucially, each of the outputs can be individually controlled. They can be individually turned on and off or powerlevels specified if set as a Dew Heater.

Fig. 5 Power Status Screen

What it is:

Fully-automated DSO imager:

The ASIAIR Plus is capable of completely automated imaging of multiple deep skytargets selected either from one of the Messier, IC, NGC and Sharpless catalogues or user-specified custom coordinates. The Plan mode sequencer is capable of automating target acquisition(via platesolving), autofocus, filter selection, guiding, meridian flips and power down at the end of the sequence.

Planetary imager:

The ASIAIR Plus supports video capture in several video formats including MP4 and AVI. (at the time of writing, .SER is not supported). ROI(Region of Interest is supported) for higher frame rates.

Live Stacking:

The ASIAIR Plus supports live stacking with calibration frames which is useful for EAA or as a preview of your image capture.

Polar Alignment:

Apart from the obvious imaging functions, the ASIAIR Plus will also perform polar alignment of your mount. In my own testing, I have discovered that this does not require direct view of the celestial poles. All it requires is two regions within 30 degrees of the poles and roughly 30-60 degrees apart in RA(right ascension). This is fantastic for me as the spot that my scope is set up does not have a direct view of the SCP and previous to using the ASIair, polar alignment was always problematic.

Fig. 6 Polar Alignment Screen

What it is not

It does not provide all of the functionality of the full-featured Windows-based applications and dedicated hardware.

Functions such as target re-centering, specifying the filter to be used for plate solving, camera cool down and warm up times, mosaic planning, start and end times based on target altitude or position in the sky, customising gain settings, using darks for guiding etc are lacking.

The dew control needs to be manually set via a slider bar. There is no dynamic control based on temperature and dew point that you get with a dedicated controller.

No support for third party hardware

At the time of writing, the ASIAIR Plus and it’s predecessors support only ZWO’s line of cameras, filter wheels and focuser.

A surprisingly large array of mounts is supported but third party camera support is limited to mainstream DSLRs primarily from Canon and Nikon.

Final Words

Put simply, the ASIAIR Plus does exactly what it was meant to do for me. It has significantly simplified my astrophotography experience both in hardware and software and made the hobby that much more enjoyable. It has several incremental improvements that set it apart from the Pro and the v1 before it.

I now can spend more time imaging or for EAA rather than constantly battling software and hardware issues. It has also enabled me to share my astronomy passion with my family and friends because the EAA experience is now so easy that even my 8 year old kids know how to use the app or SkySafari to choose a target, slew to it and take a quick snap, or even a 30 to 60 sec snap to bring out more detail and colour than would be visible in our light-polluted suburban backyard.

I know there will be experienced astrophotographers who will be sceptical about this little device and there will always be tinkerers who will object to the closed nature of the ZWO ecosystem and the relatively limited configurability but to me, those limitations are more than outweighed by its elegant simplicity and extreme ease of use.