How long to image the Jellyfish Nebula with the DwarfLab DWARF mini
From a Bortle 6 suburban sky, the DwarfLab DWARF mini needs about 3 h 56 min (944 subs of 15 s with the built-in dual-band filter) for a solid image of the Jellyfish Nebula. A quick look takes 59 min; a showpiece 16 h. Under a Bortle 3 rural sky the solid figure drops to 2 h 38 min. At Bortle 6 the limit is a mix of skyglow and read noise. In this scope's field it fills 70% 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 | 38 min151 subs | 2 h 30 min601 subs | 10 h2,403 subs |
| Bortle 2Typical dark site | 38 min153 subs | 2 h 33 min612 subs | 10 h2,445 subs |
| Bortle 3Rural | 39 min158 subs | 2 h 38 min631 subs | 11 h2,524 subs |
| Bortle 4Rural / suburban transition | 42 min170 subs | 2 h 50 min680 subs | 11 h2,717 subs |
| Bortle 5Suburban | 47 min189 subs | 3 h 09 min756 subs | 13 h3,023 subs |
| Bortle 6Bright suburban | 59 min236 subs | 3 h 56 min944 subs | 16 h3,773 subs |
| Bortle 7Suburban / urban transition | 1 h 21 min326 subs | 5 h 25 min1,301 subs | 22 h5,203 subs |
| Bortle 8City | 1 h 56 min464 subs | 7 h 44 min1,856 subs | 31 h7,423 subs |
| Bortle 9Inner city | 3 h 10 min760 subs | 13 h3,040 subs | 51 h12,158 subs |
Power and kit for this session
Allowing for slewing, focusing and rejected subs, that is about 5 h 07 min of run time. The DWARF mini’s battery is rated at about 3 h 30 min, less near freezing, so the session needs an external power bank. (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 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.
- 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 Jellyfish Nebula is 50′ × 40′ across. The DWARF mini frames 2.13° × 1.20° at 3.99″ per pixel, so it fills 70% of the frame’s short side.
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 | 2 h 38 min631 subs | 3 h 09 min756 subs | 5 h 25 min1,301 subs |
| 30 s | 1 h 51 min223 subs | 2 h 22 min285 subs | 4 h 38 min557 subs |
| 60 s | 1 h 28 min88 subs | 1 h 59 min119 subs | 4 h 15 min256 subs |
| 90 s | 1 h 20 min54 subs | 1 h 51 min75 subs | 4 h 07 min165 subs |
With and without the dual-band filter
| Filter | Bortle 3 | Bortle 5 | Bortle 7 |
|---|---|---|---|
| Astro (no light-pollution filter) | 2 h 20 min559 subs | 4 h 01 min966 subs | 11 h2,747 subs |
| dual-band | 2 h 38 min631 subs | 3 h 09 min756 subs | 5 h 25 min1,301 subs |
About the Jellyfish Nebula
A supernova remnant beside Propus in Gemini, with a bright rim like a jellyfish bell. Faint; dual-band and hours.
IC 443, Sh2-248 · Supernova remnant in Gemini · magnitude 12.0 · 50′ × 40′ · best in Dec, Jan, Feb. Reachable from mid-northern latitudes (UK, northern US, central Europe) and from the south.
Supernova remnants are emission-line objects, strong in both hydrogen-alpha and OIII, and their filaments are thin, so pixel scale matters as much as aperture. A dual-band filter is essential from any lit sky and still helps under a dark one. These are long-integration targets; plan on several sessions and stack across nights.
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 Jellyfish 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
- Jellyfish Nebula with the ZWO Seestar S50: 4 h from Bortle 6
- Jellyfish Nebula with the ZWO Seestar S50 Pro: 4 h 30 min from Bortle 6
- Jellyfish Nebula with the ZWO Seestar S30: 4 h 43 min from Bortle 6
- Jellyfish Nebula with the ZWO Seestar S30 Pro: 4 h 51 min from Bortle 6
- Jellyfish Nebula with the DwarfLab DWARF 3: 4 h 52 min from Bortle 6
- Jellyfish Nebula with the DwarfLab Draco: 3 h 09 min from Bortle 6
- Jellyfish Nebula with the DwarfLab DWARF II: 23 h from Bortle 6
- Jellyfish Nebula with the Vaonis Vespera II: 6 h 37 min from Bortle 6
- Jellyfish Nebula with the Vaonis Vespera Pro: 15 h from Bortle 6
- Jellyfish Nebula with the Vaonis Vespera 3: 6 h 19 min from Bortle 6
- Jellyfish Nebula with the Vaonis Vespera Pro 2: 14 h from Bortle 6
- Jellyfish Nebula with the Unistellar eQuinox 2: 6 h 05 min from Bortle 6
- Jellyfish Nebula with the Unistellar Odyssey: 28 h from Bortle 6
- Jellyfish Nebula with the Celestron Origin: 1 h 45 min from Bortle 6
- Jellyfish Nebula with the Celestron Origin Mark II: 2 h 23 min from Bortle 6
All telescopes for the Jellyfish Nebula · All targets for the DWARF mini