How long to image the Monkey Head Nebula with the Vaonis Vespera Pro 2
From a Bortle 6 suburban sky, the Vaonis Vespera Pro 2 needs about 5 h 46 min (2,075 subs of 10 s) for a solid image of the Monkey Head Nebula. A quick look takes 1 h 26 min; a showpiece 23 h. Under a Bortle 3 rural sky the solid figure drops to 2 h 21 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 40% 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 | 30 min182 subs | 2 h 01 min725 subs | 8 h 03 min2,899 subs |
| Bortle 2Typical dark site | 32 min192 subs | 2 h 08 min767 subs | 8 h 31 min3,065 subs |
| Bortle 3Rural | 35 min212 subs | 2 h 21 min845 subs | 9 h 23 min3,379 subs |
| Bortle 4Rural / suburban transition | 43 min259 subs | 2 h 52 min1,035 subs | 11 h4,139 subs |
| Bortle 5Suburban | 56 min334 subs | 3 h 43 min1,336 subs | 15 h5,343 subs |
| Bortle 6Bright suburban | 1 h 26 min519 subs | 5 h 46 min2,075 subs | 23 h8,299 subs |
| Bortle 7Suburban / urban transition | 2 h 25 min871 subs | 9 h 40 min3,483 subs | 39 h13,931 subs |
| Bortle 8City | 3 h 56 min1,418 subs | 16 h5,669 subs | 63 h22,675 subs |
| Bortle 9Inner city | 7 h 10 min2,583 subs | 29 h10,331 subs | 110+ h41,324 subs |
Power and kit for this session
Allowing for slewing, focusing and rejected subs, that is about 7 h 30 min of run time. That is more than one night: over 2 nights, about 3 h 45 min each. The Vespera Pro 2’s battery (rated about 11 h) should cover each night; 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 January night.)
- USB-C PD power bank 20000mAh 30WExternal bank extends the 11 h battery.
- 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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How it frames
The Monkey Head Nebula is 40′ × 30′ across. The Vespera Pro 2 frames 1.65° × 1.65° at 1.68″ per pixel, so it fills 40% 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 gives 3.2° × 3.2° at 50 MP. Time for a solid image by sub length:
| Sub length | Bortle 3 | Bortle 5 | Bortle 7 |
|---|---|---|---|
| 10 s | 2 h 21 min845 subs | 3 h 43 min1,336 subs | 9 h 40 min3,483 subs |
| 20 s | 1 h 56 min348 subs | 3 h 18 min594 subs | 9 h 16 min1,667 subs |
| 30 s | 1 h 48 min216 subs | 3 h 10 min380 subs | 9 h 07 min1,095 subs |
With and without the dual-band filter
| Filter | Bortle 3 | Bortle 5 | Bortle 7 |
|---|---|---|---|
| No filter | 2 h 21 min845 subs | 3 h 43 min1,336 subs | 9 h 40 min3,483 subs |
| dual-band (Dual Band filter), clip-on | 3 h1,081 subs | 3 h 25 min1,232 subs | 5 h 15 min1,889 subs |
The Vespera Pro 2 has no built-in dual-band filter. Optional clip-on Vaonis filters: dual-band, light-pollution (CLS) and solar. On an emission target like this it is the single biggest upgrade you can make.
About the Monkey Head Nebula
A round emission cloud on the Orion-Gemini border with a profile like a monkey's face. Moderately bright, good with dual-band.
NGC 2174, Sh2-252 · Emission nebula in Orion · magnitude 6.8 · 40′ × 30′ · best in Dec, Jan, Feb. Reachable from mid-northern latitudes (UK, northern US, central Europe) and from the south.
Emission nebulae glow in a few narrow lines, mostly hydrogen-alpha (deep red) and doubly ionised oxygen (teal). A dual-band filter passes those lines and blocks most skyglow, which is why it cuts the time needed from a suburban sky so dramatically. Use it. From a genuinely dark site the gain is smaller because there is less skyglow to block, and read noise becomes the limit, which is where longer subs (EQ mode, or Expert Mode on a Vespera) earn their keep.
Stars lose colour through a dual-band filter; a short broadband stack blended in fixes that if you care.
About the Vaonis Vespera Pro 2
The square-sensor 2026 Vespera with 2 µm pixels. Sharper than the Vespera 3 on small targets and correspondingly slower per pixel; the 12.5 MP square frame suits galaxies and planetaries.
10 s subs by default; Expert Mode manual targets allow 1 to 30 s. Alt-azimuth only; CovalENS mosaic gives 3.2° × 3.2° at 50 MP. 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 Monkey Head Nebula from a Vespera Pro 2? Email it with your total time and sky to [email protected] and it goes here, credited.
Same target, other telescopes
- Monkey Head Nebula with the ZWO Seestar S50: 1 h 41 min from Bortle 6
- Monkey Head Nebula with the ZWO Seestar S50 Pro: 1 h 53 min from Bortle 6
- Monkey Head Nebula with the ZWO Seestar S30: 1 h 58 min from Bortle 6
- Monkey Head Nebula with the ZWO Seestar S30 Pro: 2 h 02 min from Bortle 6
- Monkey Head Nebula with the DwarfLab DWARF 3: 2 h 05 min from Bortle 6
- Monkey Head Nebula with the DwarfLab DWARF mini: 1 h 40 min from Bortle 6
- Monkey Head Nebula with the DwarfLab Draco: 1 h 20 min from Bortle 6
- Monkey Head Nebula with the DwarfLab DWARF II: 9 h 16 min from Bortle 6
- Monkey Head Nebula with the Vaonis Vespera II: 2 h 42 min from Bortle 6
- Monkey Head Nebula with the Vaonis Vespera Pro: 6 h 03 min from Bortle 6
- Monkey Head Nebula with the Vaonis Vespera 3: 2 h 35 min from Bortle 6
- Monkey Head Nebula with the Unistellar eQuinox 2: 2 h 28 min from Bortle 6
- Monkey Head Nebula with the Unistellar Odyssey: 11 h from Bortle 6
- Monkey Head Nebula with the Celestron Origin: 43 min from Bortle 6
- Monkey Head Nebula with the Celestron Origin Mark II: 59 min from Bortle 6
All telescopes for the Monkey Head Nebula · All targets for the Vespera Pro 2