Given the rising popularity of robotic self-aligning instruments, there really should be a snappy acronym for a device that embodies the seamless integration of telescope, camera, image processing, object location and tracking: a ‘TECIPOLT’ just doesn’t sound right! However, I’ll wager that just as Hoover became synonymous with the vacuum cleaner, we could soon be calling these new opto-electronic marvels ‘Vesperas’ after the latest product to emerge from the talented technicians at French company Vaonis.
With their headquarters in Castelnau-le-Lez to the east of Montpellier on the Mediterranean coast, Vaonis is located less than a two-hour drive from Marseille and their principal competitor, Unistellar. The two companies appear to offer superficially similar products: computerised telescopes that automatically align themselves, track targets and use embedded image-stacking hardware, delivering near real-time pictures to a smartphone or tablet connected via Wi-Fi. However, whereas Unistellar’s products lean towards collaborative citizen science projects, those from Vaonis are primarily targeted at astro-imagers.
Vaonis’ instruments use self-focusing apochromatic lenses for their objectives, so your pictures are always sharp and bright stars are unadorned with the diffraction spikes appearing on images created by their competitors. I reviewed the ED doublet-based 80mm, f/5 (400mm focal length) Stellina in the January 2021 issue of Astronomy Now. Its smaller sibling, the über portable Vespera, uses a 50mm, f/4 apochromatic quadruplet optical system (200mm focal length).
Vespera can’t be used visually because it has no eyepiece, and an electronic detector lies at the focus of its four-element lens array. Vaonis chose a 2.1-megapixel colour Sony STARVIS IMX462 CMOS chip that has high sensitivity in visible and near-infrared light and delivers a 1.6 × 0.9 degree field of view – twice the area of its predecessor. The IMX462 sensor has 2.9-micron (0.0029mm) pixels, hence the instrument’s resolution is three arcseconds per pixel. However, Vespera doesn’t possess Stellina’s built-in ‘City Light Suppression’ (CLS) filter to mitigate light pollution – Vaonis offers a full-aperture CLS filter as a €199 optional extra instead.
Vaonis calls its products ‘observation stations’ because they offer an all-in-one solution for predominantly moderate-scale deep-sky astrophotography, in addition to full-disc imagery of the Moon and Sun (the latter with an optional full-aperture solar filter). It’s important to stress that you can’t use Vespera (or Stellina, for that matter) to zoom into individual craters on the Moon’s surface, view Jupiter’s Great Red Spot or resolve features on the disc of Mars at opposition – you need a conventional optical telescope for that.
Vespera – which, incidentally, means ‘evening’ in Latin – arrives double-boxed in a shipping carton. Inside is the instrument’s day-to-day storage: a black, foam-lined cardboard box sporting a carrying handle on the top. The internal foam has cut-outs to fit the Vespera in a slip-on case, a USB wall plug (with US, EU and UK adaptors), a 1.5-metre-long magnetic USB-C charging cable, a bubble level, a table-top tripod with detachable legs, and a quick-start card. Vespera’s closed exterior dimensions are 18cm (W) × 9cm (D) × 39cm (H) and the device tips the scales at five kilograms. The supplied tripod is just 17.5cm high when assembled. Its central hub, with a standard 3/8-inch photo thread connecting it to the base of Vespera, accepts 20cm-long screw-in tripod legs. The tips of each leg have 2.5cm-long internal threads so that you can finely adjust the tilt of the tripod once you clip the supplied magnetic bubble level onto the base of the device. Note that you can use your own sturdy full-height photo tripod if it has a standard 3/8-inch connecting thread.
Vespera’s curvaceous plastic case has a beautifully proportioned, minimalist, sculpture-like air about it. A single L-shaped gap in the casing hints that some part of Vespera folds out, but otherwise there’s nothing about its appearance that suggests an optical instrument and it would certainly be a coffee-table conversation piece. However, is this merely an example of form eclipsing function? It was time to power-up Vespera and find out.
Vaonis’ control app is called Singularity, which must be installed on a compatible smartphone or tablet to control Vespera. For initial setup a QR code on the quick-start card takes you to the App Store for Apple devices, or Google Play for those running Android. Note that your iPhone or iPad needs to support iOS version 14 and higher, or Android version 8 and above. For testing I used a sevenyear-old iPhone 6s Plus (iOS 15.7) and a year-old Lenovo tablet (Android 10). At the time of writing, the current version of Singularity is v1.10.3.
Vespera has an internal Li-Ion battery that Vaonis states will power it for up to four hours. Subsequent testing showed this was in the right ballpark, although a particularly cold night or a dewy one requiring the lens de-mister will reduce battery life considerably. The magnetic USB-C charging cable has a connector reminiscent of Apple’s MagSafe for laptops that safely unclips if you accidentally trip over it. The polarity of the cable’s magnet means that you can only connect it to Vespera one way and the power button on the side of the device pulses green every 10 seconds until it’s charged, which can take a few hours if fully discharged. You can connect an external battery pack if you wish to image throughout the night.
You activate Vespera by touching the power button on the side for a couple of seconds, its periphery pulsing blue as the instrument boots. In around 30 seconds the Wi-Fi setting of your tablet or smartphone shows an unsecured network simply called ‘vespera’, followed by a unique alphanumeric code. Once connected (no password required), the power button’s edge glows solid blue. Since Vespera is tethered to your handset’s Wi-Fi, you’ll need your phone’s 4G/5G data network to continue accessing the Internet. Incidentally, up to eight smart-devices can be connected to Vespera simultaneously, but only one is designated the controller – the others can look on and see the pictures.
Formerly known as Stellinapp, Singularity delivers a control interface that will be familiar to users of all Vaonis devices. During the course of my review the software received two major updates: Solar Mode (for observing the Sun with an appropriate objective filter), new catalogue objects and bug fixes arrived with v1.9.4 on 11 October; then v1.10.3 brought further bug fixes and ‘Mosaic Mode beta’ (the ability to automatically create tiled pictures up to four times the area of the sensor). Each time I updated the app, Singularity also wirelessly patched the instrument’s firmware without a hitch. Incidentally, Vespera’s internal computer is an Arm Cortex-A72 Raspberry Pi 4.
Singularity opens with ‘Your Space Center’ (sic), a summary weather forecast for your chosen location, the Moon’s phase, lunar and solar rising and setting times, plus some suggestions of forthcoming celestial events. You can define a number of observing locations from a gazetteer, or enter their latitude and longitude manually. Think of this opening screen as the Control section of the app where you can initialise (and shut down) Vespera.
The first time you witness initialisation is quite magical. Vespera’s internal stepper motors purr into life and the arm containing the four-element optical train and sensor glides out of its stored position and rotates up to the sky. The instrument takes time and GPS data from your smart device and automatically conducts a star zone search. Next it performs a plate-solve to determine precisely where it’s pointed, then it adjusts focus to ensure that its images are sharp. Within just a few minutes you’re ready to go!
The app’s user interface changes depending on which tab you select at the bottom of the screen: Control, Explore, Plan My Night or Profile. I mentioned Control in the paragraph above. Explore is where you select targets from a current list of about 300 objects compiled from the Messier, NGC and IC catalogues, asterisms, double stars, the Sun (with appropriate filter), Moon and planets, or you can manually enter J2000 equatorial coordinates. Vaonis is open to suggestions about objects that you wish to see added to its database and new features too.
Singularity is largely self-explanatory and intuitive to use with built-in help, but it has a few quirks. Plan My Night is a superb feature for creating automated sequences of objects for Vespera to image and for how long throughout the night – galaxies for supernova hunting, for example. But its usefulness is undermined by its inability to sequence manuallyentered objects, which is important when Singularity still has a relatively small built-in database. Thankfully, Vaonis is aware of these shortcomings and is planning future updates.
Activating Expert Mode (in ‘Parameters’ under the Profile tab) lets you create custom camera exposure and gain settings for manually entered objects. Furthermore, you can specify the image formats that you wish Vespera to save, from auto-stacked JPEGs and 16-bit TIFFs to raw 16-bit FITS files should you wish to perform your own image processing on a separate computer. The process of wireless file-sharing with Vespera is a little clunky, but it works on Windows, Mac and Linux. To give you some idea of the storage you’ll need, the file sizes generated by Vespera are around 500KB for JPEG, 4MB for each FITS frame, or up to 12MB for TIFF in full resolution.
Once you’ve selected an object to observe, and Vespera has confirmed its position by plate-solving, auto-focused to get the sharpest view and engaged tracking, then the image-processing magic starts. As each incoming 10-second-long, 20Db-gain frame (by default) is auto-rotated, registered and livestacked with the last, you see your subject slowly appear on screen before your eyes. You can save pictures to Singularity’s library, your device’s gallery or social media at any time. What’s amazing is how clean Vespera’s images are with minimal hot pixels, considering that the sensor is uncooled and no darkframe subtraction is performed.
Some bright nebulae such as the Orion Nebula (M42) or the Dumbbell (M27) are recognisable, colourful and richly structured after tens of seconds. Conversely, faint emission nebulae or supernova remnants such as the Veil Nebula in Cygnus can take an hour to capture. You can replay a whole stack of frames from the start, pan around or zoom in and out of the image on your smart device using pinch and spread gestures, even as it is stacking. Never once did Singularitycrash or freeze on me.
Vespera’s objective incorporates a built-in lens heater to prevent dew and it is undoubtedly effective. However, the hygrometric sensor required to activate it is a €99 optional extra! Perhaps this reflects the mentality of a company based in sun-drenched southern France, but anyone living in the British Isles contemplating buying a Vespera should argue that it be bundled with the instrument. The sensor is button-sized and installed next to the objective lens with a tiny screw to secure it in place. Singularity senses its presence and provides you with temperature and humidity data in the app.
Solar and Mosaic modes
Introduced in the software update on 11 October, the ability to observe the Sun with its €99 optional full-aperture solar filter is well worth the price of admission, extending your investment’s use into the daytime. Since Vespera’s normal plate-solving alignment methods are unavailable during the day, Singularity walks you through the procedure of safely pointing the instrument manually near the Sun as the first point of reference, whereupon the instrument takes over and performs an automated solar-seeking and focusing routine. It worked flawlessly for me, and I had great fun recording the partial solar eclipse of 25 October, sharing it in near real-time with friends over WhatsApp. Despite Vespera’s three-arcsecond resolution, I could still see solar granulation, structure in the sunspots on view and the Moon’s irregular limb.
As if Solar Mode wasn’t enough, Vaonis pulled out all the stops to deliver Mosaic Mode on 27 October. Vespera (and Stellina) users can now automatically create seamless image mosaics. I only received this update mere days before the magazine’s review deadline and had one night to test it on the Pleiades under a very hazy sky, but it appeared to work as designed.
Once you’ve selected a deep-sky object and requested a mosaic rather than a conventional observation, you’re offered a graphic of the region with a customisable framing area, the proportions of which you can change and rotate, up to an area four times Vespera’s 1.6-degree by 0.9-degree field of view. Hence you can select a square 2.4 × 2.4 degrees, or 3.2 × 1.8 degrees, or something tall and thin or wide and flat. This is a tremendously useful and exciting feature with lots of potential for recording near-Earth asteroid tracks, for example.
Coming from a long-time visual observing and, for the last 15 years or so, imaging background, I have to admit that I came to Vespera with a mindset slightly dismissive of its capabilities. Now having spent a decent interval using it on a wide range of subjects under varied skies, I’ve become a total convert. Devices such as Vespera often receive disparaging comments from traditional astroimagers saying that their set-up was a fraction of the cost and has greater capabilities, etc, but not everyone wishing to capture attractive images of deep-sky objects has the time or the inclination to ascend the steep learning curve of traditional astrophotography.
Vespera is self-contained and so compact that you will take it just about anywhere, capturing pleasing views of a couple of objects in the time a conventional astro-imager is still aligning and calibrating their equipment. Vaonis and their control software Singularity pull off a neat trick in making sophisticated astrophotography accessible to the novice, yet providing enough advanced features to keep seasoned imagers happy.