How long to image the North America Nebula with the DwarfLab DWARF mini
From a Bortle 6 suburban sky, the DwarfLab DWARF mini needs about 1 h 24 min (336 subs of 15 s with the built-in dual-band filter) for a solid image of the North America Nebula. A quick look takes 21 min; a showpiece 5 h 36 min. Under a Bortle 3 rural sky the solid figure drops to 58 min. At Bortle 6 the limit is a mix of skyglow and read noise. In this scope's field it is 1.7× wider than the frame.
| Sky | Quick lookTarget obvious, still noisy | SolidClean enough to share | ShowpieceSmooth faint detail, print-worthy |
|---|---|---|---|
| Bortle 1Excellent dark site | 14 min56 subs | 56 min223 subs | 3 h 42 min890 subs |
| Bortle 2Typical dark site | 14 min57 subs | 56 min226 subs | 3 h 46 min904 subs |
| Bortle 3Rural | 15 min59 subs | 58 min233 subs | 3 h 53 min931 subs |
| Bortle 4Rural / suburban transition | 16 min63 subs | 1 h 02 min249 subs | 4 h 09 min995 subs |
| Bortle 5Suburban | 17 min69 subs | 1 h 08 min274 subs | 4 h 34 min1,096 subs |
| Bortle 6Bright suburban | 21 min84 subs | 1 h 24 min336 subs | 5 h 36 min1,344 subs |
| Bortle 7Suburban / urban transition | 28 min114 subs | 1 h 54 min455 subs | 7 h 34 min1,818 subs |
| Bortle 8City | 40 min160 subs | 2 h 40 min639 subs | 11 h2,553 subs |
| Bortle 9Inner city | 1 h 04 min258 subs | 4 h 18 min1,031 subs | 17 h4,121 subs |
Power and kit for this session
Allowing for slewing, focusing and rejected subs, that is about 1 h 49 min of run time. The DWARF mini’s battery (rated about 3 h 30 min) 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 10000mAh 20W7,000 mAh inside, about four hours; a PD bank extends the night.
- 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 DWARF mini →
How it frames
The North America Nebula is 120′ × 100′ across. The DWARF mini frames 2.13° × 1.20° at 3.99″ per pixel, so it is 1.7× wider than the frame. A mosaic, or choosing the part you want and letting the rest go, is how it gets shot on this scope.
Longer subs
Auto mode caps subs at 15 s; 30 s and longer need EQ mode, and 90 s is the ceiling. Time for a solid image by sub length:
| Sub length | Bortle 3 | Bortle 5 | Bortle 7 |
|---|---|---|---|
| 15 s | 58 min233 subs | 1 h 08 min274 subs | 1 h 54 min455 subs |
| 30 s | 43 min86 subs | 53 min106 subs | 1 h 38 min197 subs |
| 60 s | 35 min35 subs | 45 min46 subs | 1 h 30 min91 subs |
| 90 s | 45 min30 subs | 45 min30 subs | 1 h 28 min59 subs |
With and without the dual-band filter
| Filter | Bortle 3 | Bortle 5 | Bortle 7 |
|---|---|---|---|
| Astro (no light-pollution filter) | 50 min202 subs | 1 h 24 min337 subs | 3 h 51 min926 subs |
| dual-band | 58 min233 subs | 1 h 08 min274 subs | 1 h 54 min455 subs |
About the North America Nebula
A huge emission cloud next to Deneb shaped like the continent. The Cygnus Wall is the bright bit; a dual-band filter and a wide field make it one of the best summer targets from town.
NGC 7000, Caldwell 20 · Emission nebula in Cygnus · magnitude 4.0 · 120′ × 100′ · best in Jul, Aug, Sep. 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 DwarfLab DWARF mini
DwarfLab’s answer to the Seestar S30: same sensor and focal length, big pixels, dual-band filter built in, and 90 s subs in EQ mode. Sensitivity over megapixels.
Auto mode caps subs at 15 s; 30 s and longer need EQ mode, and 90 s is the ceiling. Built-in Astro (430 to 690 nm), dark-frame and dual-band Hα / OIII filters; no plain VIS filter on the tele camera.
Longer subs matter most under dark skies, where read noise rather than skyglow sets the floor. From a city the difference between 15 s and 90 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 North America Nebula from a DWARF mini? Email it with your total time and sky to [email protected] and it goes here, credited.
Same target, other telescopes
- North America Nebula with the ZWO Seestar S50: 1 h 25 min from Bortle 6
- North America Nebula with the ZWO Seestar S50 Pro: 1 h 36 min from Bortle 6
- North America Nebula with the ZWO Seestar S30: 1 h 39 min from Bortle 6
- North America Nebula with the ZWO Seestar S30 Pro: 1 h 43 min from Bortle 6
- North America Nebula with the DwarfLab DWARF 3: 1 h 46 min from Bortle 6
- North America Nebula with the DwarfLab Draco: 1 h 08 min from Bortle 6
- North America Nebula with the DwarfLab DWARF II: 7 h 45 min from Bortle 6
- North America Nebula with the Vaonis Vespera II: 2 h 15 min from Bortle 6
- North America Nebula with the Vaonis Vespera Pro: 5 h 04 min from Bortle 6
- North America Nebula with the Vaonis Vespera 3: 2 h 09 min from Bortle 6
- North America Nebula with the Vaonis Vespera Pro 2: 4 h 49 min from Bortle 6
- North America Nebula with the Unistellar eQuinox 2: 2 h 04 min from Bortle 6
- North America Nebula with the Unistellar Odyssey: 9 h 33 min from Bortle 6
- North America Nebula with the Celestron Origin: 36 min from Bortle 6
- North America Nebula with the Celestron Origin Mark II: 49 min from Bortle 6
All telescopes for the North America Nebula · All targets for the DWARF mini