How long to image the Black Eye Galaxy with the Vaonis Vespera Pro
From a Bortle 6 suburban sky, the Vaonis Vespera Pro needs about 1 h 16 min (459 subs of 10 s) for a solid image of the Black Eye Galaxy. A quick look takes 19 min; a showpiece 5 h 05 min. Under a Bortle 3 rural sky the solid figure drops to 36 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 10% 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 | 8 min49 subs | 32 min193 subs | 2 h 08 min769 subs |
| Bortle 2Typical dark site | 8 min51 subs | 33 min201 subs | 2 h 14 min802 subs |
| Bortle 3Rural | 9 min54 subs | 36 min216 subs | 2 h 24 min864 subs |
| Bortle 4Rural / suburban transition | 11 min64 subs | 42 min254 subs | 2 h 49 min1,013 subs |
| Bortle 5Suburban | 13 min79 subs | 52 min313 subs | 3 h 28 min1,251 subs |
| Bortle 6Bright suburban | 19 min115 subs | 1 h 16 min459 subs | 5 h 05 min1,833 subs |
| Bortle 7Suburban / urban transition | 31 min184 subs | 2 h 03 min736 subs | 8 h 10 min2,942 subs |
| Bortle 8City | 49 min292 subs | 3 h 14 min1,166 subs | 13 h4,664 subs |
| Bortle 9Inner city | 1 h 27 min522 subs | 5 h 47 min2,085 subs | 23 h8,337 subs |
Power and kit for this session
Allowing for slewing, focusing and rejected subs, that is about 1 h 39 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.)
- 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.
Affiliate links: the retailer pays us a small commission and you pay the same price. These are search links to the named product, not endorsements of a particular listing; check the listing matches your model.
Everything that fits the Vespera Pro →
How it frames
The Black Eye Galaxy is 10′ × 5′ across. The Vespera Pro frames 1.62° × 1.62° at 1.65″ per pixel, so it fills 10% 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 | 36 min216 subs | 52 min313 subs | 2 h 03 min736 subs |
| 20 s | 31 min93 subs | 47 min142 subs | 1 h 57 min353 subs |
| 30 s | 29 min59 subs | 45 min91 subs | 1 h 56 min232 subs |
About the Black Eye Galaxy
A bright spiral with a dark dust band across the nucleus. The eye shows within an hour on a 50 mm scope.
M64, NGC 4826 · Galaxy in Coma Berenices · magnitude 8.5 · 10′ × 5′ · best in Mar, Apr, May. 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 Black Eye Galaxy from a Vespera Pro? Email it with your total time and sky to [email protected] and it goes here, credited.
Same target, other telescopes
- Black Eye Galaxy with the ZWO Seestar S50: 34 min from Bortle 6
- Black Eye Galaxy with the ZWO Seestar S50 Pro: 37 min from Bortle 6
- Black Eye Galaxy with the ZWO Seestar S30: 36 min from Bortle 6
- Black Eye Galaxy with the ZWO Seestar S30 Pro: 40 min from Bortle 6
- Black Eye Galaxy with the DwarfLab DWARF 3: 50 min from Bortle 6
- Black Eye Galaxy with the DwarfLab DWARF mini: 34 min from Bortle 6
- Black Eye Galaxy with the DwarfLab Draco: 28 min from Bortle 6
- Black Eye Galaxy with the DwarfLab DWARF II: 1 h 55 min from Bortle 6
- Black Eye Galaxy with the Vaonis Vespera II: 34 min from Bortle 6
- Black Eye Galaxy with the Vaonis Vespera 3: 33 min from Bortle 6
- Black Eye Galaxy with the Vaonis Vespera Pro 2: 1 h 13 min from Bortle 6
- Black Eye Galaxy with the Unistellar eQuinox 2: 30 min from Bortle 6
- Black Eye Galaxy with the Unistellar Odyssey: 2 h 18 min from Bortle 6
- Black Eye Galaxy with the Celestron Origin: 9 min from Bortle 6
- Black Eye Galaxy with the Celestron Origin Mark II: 13 min from Bortle 6
All telescopes for the Black Eye Galaxy · All targets for the Vespera Pro