How long to image the Triangulum Galaxy with the Vaonis Vespera 3
From a Bortle 6 suburban sky, the Vaonis Vespera 3 needs about 2 h 35 min (928 subs of 10 s) for a solid image of the Triangulum Galaxy. A quick look takes 39 min; a showpiece 10 h. Under a Bortle 3 rural sky the solid figure drops to 57 min. At Bortle 6 the limit is skyglow, so a darker site or a filter helps more than longer subs. In this scope's field it fills 83% of the frame’s short side.
| Sky | Quick lookTarget obvious, still noisy | SolidClean enough to share | ShowpieceSmooth faint detail, print-worthy |
|---|---|---|---|
| Bortle 1Excellent dark site | 12 min72 subs | 48 min286 subs | 3 h 10 min1,141 subs |
| Bortle 2Typical dark site | 13 min77 subs | 51 min305 subs | 3 h 23 min1,220 subs |
| Bortle 3Rural | 14 min86 subs | 57 min343 subs | 3 h 48 min1,369 subs |
| Bortle 4Rural / suburban transition | 18 min109 subs | 1 h 12 min433 subs | 4 h 48 min1,731 subs |
| Bortle 5Suburban | 24 min144 subs | 1 h 36 min576 subs | 6 h 24 min2,304 subs |
| Bortle 6Bright suburban | 39 min232 subs | 2 h 35 min928 subs | 10 h3,709 subs |
| Bortle 7Suburban / urban transition | 1 h 07 min400 subs | 4 h 26 min1,597 subs | 18 h6,388 subs |
| Bortle 8City | 1 h 50 min660 subs | 7 h 19 min2,637 subs | 29 h10,547 subs |
| Bortle 9Inner city | 3 h 22 min1,214 subs | 13 h4,855 subs | 54 h19,417 subs |
Power and kit for this session
Allowing for slewing, focusing and rejected subs, that is about 3 h 21 min of run time. The Vespera 3’s battery (rated about 11 h) should cover it; a power bank still keeps the phone running the app alive. (Bortle 6, solid image; we allow 30% over the integration time.)
- USB-C PD power bank 20000mAh 30WVaonis says an external bank extends sessions; 30 W PD as for the II and Pro.
- red LED head torchRed light keeps your night vision; white light costs you twenty minutes of dark adaptation every time.
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Everything that fits the Vespera 3 →
How it frames
The Triangulum Galaxy is 73′ × 45′ across. The Vespera 3 frames 2.60° × 1.46° at 2.44″ per pixel, so it fills 83% of the frame’s short side.
Longer subs
10 s subs by default; Expert Mode manual targets allow 1 to 30 s. Alt-azimuth only; CovalENS mosaic widens the field to 4.3° × 2.4°. Time for a solid image by sub length:
| Sub length | Bortle 3 | Bortle 5 | Bortle 7 |
|---|---|---|---|
| 10 s | 57 min343 subs | 1 h 36 min576 subs | 4 h 26 min1,597 subs |
| 20 s | 48 min145 subs | 1 h 27 min262 subs | 4 h 17 min773 subs |
| 30 s | 45 min91 subs | 1 h 24 min169 subs | 4 h 14 min509 subs |
About the Triangulum Galaxy
Big, face-on and low in surface brightness. Nearly as bright as M31 overall but spread thin, so it needs far more time. Its H II regions pop with a dual-band filter.
M33, NGC 598 · Galaxy in Triangulum · magnitude 5.7 · 73′ × 45′ · best in Sep, Oct, Nov. Reachable from mid-northern latitudes (UK, northern US, central Europe) and from the south.
Galaxies are broadband targets: their light is mostly starlight spread across the spectrum, so a dual-band filter throws most of it away and makes things slower, not faster. Shoot without a filter (or with a plain UV/IR cut) and rely on total time and a dark sky. The core of a galaxy is usually many times brighter than its outer disc, so a short stack shows the nucleus long before the arms; the figures here are for the arms and disc, not the core.
Field rotation in Alt-Az mode crops the edges of the stack over a long session, so on a big galaxy re-centre now and then or use EQ mode where your scope supports it.
About the Vaonis Vespera 3
The 2026 Vespera: same 50 mm quadruplet class as the II on an 8 MP IMX585, with a 24 MP mosaic mode and 11 hours of battery. Per pixel it behaves like a Seestar S50 Pro without the built-in dual-band filter.
10 s subs by default; Expert Mode manual targets allow 1 to 30 s. Alt-azimuth only; CovalENS mosaic widens the field to 4.3° × 2.4°. Optional clip-on Vaonis filters: dual-band, light-pollution (CLS) and solar. The new optical baffle is not a substitute for a CLS filter.
Longer subs matter most under dark skies, where read noise rather than skyglow sets the floor. From a city the difference between 10 s and 30 s subs is small; from a rural site it can halve the total time, especially with a dual-band filter in place.
Stack across nights. Every smart scope app can continue a stack or you can combine the saved frames on a computer; the figures here are totals, not single-session limits.
Have an image of the Triangulum Galaxy from a Vespera 3? Email it with your total time and sky to [email protected] and it goes here, credited.
Same target, other telescopes
- Triangulum Galaxy with the ZWO Seestar S50: 2 h 42 min from Bortle 6
- Triangulum Galaxy with the ZWO Seestar S50 Pro: 2 h 57 min from Bortle 6
- Triangulum Galaxy with the ZWO Seestar S30: 2 h 50 min from Bortle 6
- Triangulum Galaxy with the ZWO Seestar S30 Pro: 3 h 08 min from Bortle 6
- Triangulum Galaxy with the DwarfLab DWARF 3: 3 h 55 min from Bortle 6
- Triangulum Galaxy with the DwarfLab DWARF mini: 2 h 41 min from Bortle 6
- Triangulum Galaxy with the DwarfLab Draco: 2 h 13 min from Bortle 6
- Triangulum Galaxy with the DwarfLab DWARF II: 9 h 16 min from Bortle 6
- Triangulum Galaxy with the Vaonis Vespera II: 2 h 42 min from Bortle 6
- Triangulum Galaxy with the Vaonis Vespera Pro: 6 h 03 min from Bortle 6
- Triangulum Galaxy with the Vaonis Vespera Pro 2: 5 h 46 min from Bortle 6
- Triangulum Galaxy with the Unistellar eQuinox 2: 2 h 28 min from Bortle 6
- Triangulum Galaxy with the Unistellar Odyssey: 11 h from Bortle 6
- Triangulum Galaxy with the Celestron Origin: 43 min from Bortle 6
- Triangulum Galaxy with the Celestron Origin Mark II: 59 min from Bortle 6
All telescopes for the Triangulum Galaxy · All targets for the Vespera 3