Two smart telescopes now on pre-order finally push past the 50 mm aperture that every Seestar uses. The Vaonis Atlas, announced on October 15, carries an 80 mm f/4.5 module for $3,990 on pre-order (until November 15, then $4,990), with deliveries due in March 2027. The DWARFLAB Draco, which opened for orders in September, is a 90 mm f/3.8 for $1,599 in its SHO Edition, and new orders are quoted at roughly three months to ship. I haven’t touched either one, so this is spec-sheet arithmetic from someone who has run a 50 mm Seestar S50 off a Bortle 7 balcony in Nicosia for most of a year. In short, the extra aperture gets you to the same image in roughly a third of the time and puts about 1.5 times as many pixels across a small galaxy. It doesn’t make a nebula any brighter per pixel. On paper, Draco is the better buy for a city balcony at well under half the Atlas price.
The spec sheets side by side
I’ve put my S50 in the first column as the baseline, plus Sky-Watcher’s ORBIS 60EDX, which was shown as a prototype at the Imaging World show in Nuremberg on October 2–4 but has no price yet.
| Seestar S50 (mine) | Vaonis Atlas 80 | DWARFLAB Draco | Sky-Watcher ORBIS 60EDX | |
|---|---|---|---|---|
| Aperture | 50 mm | 80 mm, apo quadruplet | 90 mm, folded design | 60 mm, ED quadruplet |
| Focal length | 250 mm (f/5) | 360 mm (f/4.5) | 340 mm (f/3.8) | 300 mm (f/5) |
| Main sensor | IMX462, 1920 × 1080, 2.9 µm | IMX585, 3840 × 2160, 2.9 µm | 50.33 MP 1/1.3-inch, 1.197 µm (2.394 µm binned 2×2) | IMX585 (reported) |
| Pixel scale | 2.39″ | 1.66″ | 1.45″ binned, 0.73″ native | 1.99″ (my arithmetic) |
| Native field | 1.28° × 0.72° | 1.78° × 1.00° | 2.06° diagonal | 2.1° × 1.2° (reported) |
| Long exposures | alt-az, short subs | alt-az; equatorial table due H2 2027 | rotating sensor, subs up to 300 s | derotator, ±180° (reported) |
| Cooling | none | dew heater | active sensor cooling | not stated |
| Weight | one-hand carry | 6.5 kg | 5.5 kg + 480 g tripod | not stated |
| Battery | 6,000 mAh | about 6 h | 10,000 mAh, about 5 h | not stated |
| Price | $499 (discontinued) | $3,990 pre-order / $4,990 | $1,599 SHO (Standard $1,399, not taking orders) | not announced |
| Ships | n/a | March 2027 | about 3 months | summer 2027 target |
The Atlas numbers come from Space.com’s launch writeup and astro.pics, which also gives UK pricing of £3,399 at Clifton Cameras. The Draco figures are from Astronomics’ product page, which notes that DWARFLAB has stopped taking orders for the $1,399 Standard Edition. ORBIS details come from distributor posts collected by ScopeTrader, and Sky-Watcher hasn’t published an official spec sheet, so treat that column as reported. The pixel scales are my own arithmetic, 206.265 × pixel size (µm) ÷ focal length (mm), and the Atlas figure matches the 1.66″ per pixel that Clifton quotes.
What 80 or 90 mm actually buys
Light grasp goes with the square of the aperture. Compared with 50 mm, 80 mm collects (80 ÷ 50)² = 2.56 times the light, and 90 mm collects 3.24 times. There’s a caveat on Draco: a folded light path means a central obstruction, and DWARFLAB doesn’t publish its size. ScopeTrader makes the same point. Treat 3.24× as the ceiling.
Where those photons go is the part I’d want any S50 owner to understand before spending $1,600 or $4,000. On an extended object like a nebula, the signal each pixel gets depends on pixel size and focal ratio, so it scales as (pixel ÷ f-ratio)². Run the numbers:
- Atlas: (2.9 ÷ 4.5)² against the S50’s (2.9 ÷ 5)² comes to 1.23 times the S50’s per-pixel signal.
- Draco binned: (2.394 ÷ 3.78)² comes to 1.19 times.
So a single frame of the Veil Nebula from either scope is only about 20% brighter per pixel than my S50 frame. Both designs spend most of the extra light on a finer pixel scale, putting more pixels across the same patch of sky.
That’s a real gain, just a different one from what most people picture. If you downsample an Atlas or Draco stack to the S50’s 2.39″ pixels, it reaches the same signal-to-noise ratio in (50 ÷ 80)² = 39% of the integration time for the Atlas, or (50 ÷ 90)² = 31% for Draco, ignoring that obstruction. A two-hour S50 stack becomes roughly 47 minutes on an Atlas, or 37 on a Draco. Or you can keep the finer sampling and spend the time on detail.
The Atlas Twin, which takes two 80 mm modules on one dock ($5,490 pre-order, $6,990 later), doubles the collecting area again. Two 80 mm modules together match the area of a single 113 mm lens.
Pixel scale: small galaxies and planets
The finer sampling shows up best on small targets. M51, the Whirlpool, is about 11.2 arcminutes long, or 672 arcseconds:
- S50, at 2.39″ per pixel: about 280 pixels end to end
- Atlas, at 1.66″: about 400 pixels
- Draco binned, at 1.45″: about 460 pixels
Seeing caps how much of that you keep. You want the star image (its FWHM, the full width at half maximum) to span roughly two pixels or more, so 1.45″ pixels stay useful only while seeing holds at about 3″ or better. A rooftop in a warm city often won’t manage that. At 0.73″ per pixel, Draco’s native full-resolution mode is heavily oversampled for deep sky under any amateur seeing. It’s built for lucky imaging of the planets, where you shoot thousands of very short frames and keep the sharpest.
Jupiter is the test case for this winter. JPL Horizons gives it an apparent diameter of 45.2 arcseconds at its February 2027 opposition. That’s about 19 pixels across on my S50, enough for the two main belts and little else, 27 on the Atlas, 31 on Draco binned, and 62 on Draco’s native readout. The diffraction limits run in the same order: the Dawes limit, 116 ÷ aperture in mm, is 2.3″ at 50 mm, 1.45″ at 80 mm and 1.3″ at 90 mm. Of these, only Draco ships with a sampling mode that can use its full resolving power on a planet. Vaonis says a dedicated planetary module is next for the Atlas, but there’s no date or price for it yet.
Field of view: neither holds the Rosette
The Atlas 80 frames 1.78° × 1.00°, which works out to a 2.03° diagonal. DWARFLAB quotes a 2.06° diagonal for Draco. If the sensor has the usual 4:3 shape, that comes to about 1.65° × 1.24°. Either way, the two have nearly the same field, about 1.4 times the S50’s diagonal and well short of the S50 Pro’s 2.45° × 1.38°.
For balcony targets, that cuts both ways. Small galaxies, planetary nebulae and globular clusters all get the extra pixels described above. Big nebulae don’t fit. The Rosette, about 1.3° across, overflows the Atlas’s 1.00° short axis and only just squeezes into Draco’s estimated 1.24°. Andromeda, at about 3.2° × 1°, is a mosaic job on both. If framing is what bothers you about your 50 mm Seestar, the scopes I covered in the S50 Pro piece and the 30 mm Seestar piece fix it for a fraction of the money.
Field rotation and the 300-second sub
An alt-azimuth mount tracks the target but not the sky’s rotation, so over a long exposure the field turns around the frame centre. At Nicosia’s latitude (35.2° N), the rotation rate on the meridian is 15.04°/h × cos(latitude) ÷ cos(altitude). For a target at 45° altitude, that’s about 17°/h. In a 10-second Seestar sub, the corners of a 2° field shift by about 3 arcseconds, which is why short subs work. In a 300-second sub, the field turns about 1.5°, and the frame corners drift about 94″, or roughly 65 Draco pixels. Draco handles this by physically rotating the sensor to follow the sky, with a 4.09 MP monochrome guide camera correcting tracking errors. That’s how DWARFLAB can quote 300-second subs on an alt-az base without polar alignment. ORBIS is reported to have a derotator as well. The Atlas has neither for now, so long exposures wait for its equatorial table in the second half of 2027.
From a Bortle 7 balcony, though, long subs gain you less than the headline number suggests. With a broadband filter, the light-polluted sky swamps the read noise of a modern CMOS sensor within seconds, and beyond that point longer subs add little signal-to-noise per hour of imaging. They start to pay off once you put a narrow filter in front of the sensor, and Draco has one of those too: a dual-narrowband Hα + O III filter with 13 nm passbands, against the 20 nm Hα and 30 nm O III of the Seestar’s dual-band filter. Sky background through a passband scales roughly with its width, so Draco lets through about two-thirds as much skyglow at Hα as the Seestar does, and under half as much at O III. For emission nebulae from a city, that filter and the long subs it allows are worth more than the extra aperture. The SHO Edition adds an S II + O III filter for Hubble-palette colour.
The Cyprus factor: heat
In June I saw what a 30 °C night does to an uncooled Seestar sensor: hot pixels across the Veil Nebula, and M51’s outer arms fading into the noise well before they do in March. The cooled-camera piece has the numbers. Dark current roughly doubles for every 5.8 °C, and that hurts most on exactly the long narrowband subs Draco is designed for. DWARFLAB lists active sensor cooling and rates the unit for −20 to 45 °C. None of the Atlas listings I’ve found mention sensor cooling, only a humidity-controlled dew heater and an operating range of −20 to 40 °C. If the Atlas 80 really is uncooled, a Mediterranean summer will cost it some of its aperture advantage. That’s an inference from missing specs rather than a measurement, and Vaonis may yet publish one.
Sky-Watcher ORBIS: the one with an eyepiece
ORBIS is a different idea. A flip mirror sends the light from its 60 mm f/5 ED objective either to the camera or to a 1.25-inch eyepiece, reportedly a 5–16 mm zoom, which on a 300 mm focal length gives 19× to 60×. The 60ED model reportedly uses a 2.1 MP IMX662, and the 60EDX an 8.3 MP IMX585 plus a wide-angle camera. It collects 1.44 times the light of a 50 mm scope. Sky-Watcher’s regional target is summer 2027, and there’s no price yet. For a family that wants a real look through an eyepiece at Saturn’s rings and an automated imager in the same box, it’s the most interesting of the three. As an imaging upgrade from an S50, it’s too small a step to judge until it ships.
Who should skip each one
Skip the Atlas if:
- you mostly image large nebulae. Its 1.00° short axis is narrower than the S50 Pro’s.
- you image through warm summers and can’t confirm sensor cooling before you buy.
- you aren’t comfortable paying $3,990 in October for a telescope that ships in March, with no independent reviews and a modular range that so far consists of one module.
Skip Draco if:
- you carry the scope down stairs or up a mountain often. At 6 kg with the tripod, it’s more than twice the weight of an S50 Pro.
- you want to look through an eyepiece. Wait for ORBIS.
- you need a review before you pay. As of today there are no owner images and no independent measurements of the obstruction, the derotator or the cooling.
Skip both if your 50 mm scope’s real problem is field of view or battery life. A wider-field Seestar or a power bank fixes those for far less.
What I’m doing
By cost per square millimetre of aperture, Draco is about $0.25, the S50 Pro $0.51, and the Atlas $0.79 even at its pre-order price. Draco’s feature list also lines up almost point for point with what a hot, light-polluted balcony punishes: a narrow dual-band filter, long derotated subs and a cooled sensor. The Atlas’s selling point is modules that don’t exist yet.
I’m not pre-ordering either this month. Before I spend $1,599, I want one owner’s raw FITS of a small galaxy from a Bortle 7 or brighter site, plus a summer-night dark frame showing whether the cooling holds the sensor down at 30 °C. The Atlas pre-order discount runs out on November 15, four months before the first deliveries. Paying it now is a bet on Vaonis’s roadmap more than a telescope purchase. My S50 goes back out tonight. With M33 climbing in the east this month, it still has more galaxy than my balcony sky can give it.