How long to image the M77 with the Vaonis Vespera Pro
From a Bortle 6 suburban sky, the Vaonis Vespera Pro needs about 1 h 07 min (403 subs of 10 s) for a solid image of the M77. A quick look takes 17 min; a showpiece 4 h 28 min. Under a Bortle 3 rural sky the solid figure drops to 33 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 7% 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 | 7 min45 subs | 30 min180 subs | 2 h718 subs |
| Bortle 2Typical dark site | 8 min47 subs | 31 min187 subs | 2 h 04 min746 subs |
| Bortle 3Rural | 8 min50 subs | 33 min200 subs | 2 h 13 min798 subs |
| Bortle 4Rural / suburban transition | 10 min58 subs | 38 min231 subs | 2 h 34 min923 subs |
| Bortle 5Suburban | 12 min71 subs | 47 min281 subs | 3 h 07 min1,122 subs |
| Bortle 6Bright suburban | 17 min101 subs | 1 h 07 min403 subs | 4 h 28 min1,610 subs |
| Bortle 7Suburban / urban transition | 26 min159 subs | 1 h 46 min635 subs | 7 h 03 min2,540 subs |
| Bortle 8City | 41 min249 subs | 2 h 46 min996 subs | 11 h3,984 subs |
| Bortle 9Inner city | 1 h 14 min442 subs | 4 h 54 min1,766 subs | 20 h7,063 subs |
Power and kit for this session
Allowing for slewing, focusing and rejected subs, that is about 1 h 27 min of run time. The Vespera Pro’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, and 30% off the battery for a November night.)
- USB-C PD power bank 20000mAh 30WExtends the 11 h battery; 30 W PD per Vaonis.
- red LED head torchRed light keeps your night vision; white light costs you twenty minutes of dark adaptation every time.
- hand warmers long lastingAir-activated packs give hours of heat for the person; winter nights are long and you spend most of them standing still.
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Everything that fits the Vespera Pro →
How it frames
The M77 is 7′ × 6′ across. The Vespera Pro frames 1.62° × 1.62° at 1.65″ per pixel, so it fills 7% 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, no EQ mode. Time for a solid image by sub length:
| Sub length | Bortle 3 | Bortle 5 | Bortle 7 |
|---|---|---|---|
| 10 s | 33 min200 subs | 47 min281 subs | 1 h 46 min635 subs |
| 20 s | 29 min87 subs | 42 min128 subs | 1 h 42 min305 subs |
| 30 s | 28 min56 subs | 41 min83 subs | 1 h 40 min201 subs |
About the M77
A Seyfert galaxy with a blazing core and faint outer arms. The nucleus is easy; the arms are not.
NGC 1068 · Galaxy in Cetus · magnitude 8.9 · 7′ × 6′ · best in Oct, Nov, Dec. 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 Pro
The square-sensor Vespera with 2 µm pixels. Higher resolution than the II, and correspondingly slower per pixel: expect around double the time for the same per-pixel SNR. Run-out in 2026 and replaced by the Vespera Pro 2.
10 s subs by default; Expert Mode manual targets allow 1 to 30 s. Alt-azimuth only, no EQ mode. Optional clip-on Vaonis filters: dual-band, light-pollution (CLS) and solar.
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 M77 from a Vespera Pro? Email it with your total time and sky to [email protected] and it goes here, credited.
Same target, other telescopes
- M77 with the ZWO Seestar S50: 30 min from Bortle 6
- M77 with the ZWO Seestar S50 Pro: 33 min from Bortle 6
- M77 with the ZWO Seestar S30: 32 min from Bortle 6
- M77 with the ZWO Seestar S30 Pro: 35 min from Bortle 6
- M77 with the DwarfLab DWARF 3: 44 min from Bortle 6
- M77 with the DwarfLab DWARF mini: 30 min from Bortle 6
- M77 with the DwarfLab Draco: 25 min from Bortle 6
- M77 with the DwarfLab DWARF II: 1 h 41 min from Bortle 6
- M77 with the Vaonis Vespera II: 30 min from Bortle 6
- M77 with the Vaonis Vespera 3: 29 min from Bortle 6
- M77 with the Vaonis Vespera Pro 2: 1 h 04 min from Bortle 6
- M77 with the Unistellar eQuinox 2: 26 min from Bortle 6
- M77 with the Unistellar Odyssey: 1 h 59 min from Bortle 6
- M77 with the Celestron Origin: 8 min from Bortle 6
- M77 with the Celestron Origin Mark II: 11 min from Bortle 6
All telescopes for the M77 · All targets for the Vespera Pro