DwarfLab Dwarf 3: how long to image deep-sky targets
Small pixels on a 35 mm f/4.3 lens give a sharper image than its aperture suggests, and EQ mode with 60 s subs makes it the read-noise winner in dark skies.
| Spec | Value |
|---|---|
| Aperture | 35 mm |
| Focal length | 150 mm (f/4.3) |
| Sensor | Sony IMX678, 3840 × 2160, 2 µm pixels |
| Pixel scale | 2.75″ per pixel |
| Field of view | 2.93° × 1.65° (176′ × 99′) |
| Sub exposures | 15 s, 30 s, 60 s (default 15 s) |
| Filter | Built-in filter wheel with Astro (UV/IR) and dual-band filters. |
| Read noise used | 1 e⁻ |
Popular targets
| Target | Bortle 4 | Bortle 6 | Bortle 8 |
|---|---|---|---|
| Andromeda GalaxyGalaxy | 1 h 07 min270 subs | 2 h 17 min550 subs | 6 h 19 min1,517 subs |
| Orion NebulaEmission nebula, dual-band | 16 min66 subs | 20 min80 subs | 33 min132 subs |
| PleiadesReflection nebula | 2 h 01 min486 subs | 4 h 14 min1,017 subs | 12 h2,850 subs |
| Whirlpool GalaxyGalaxy | 47 min188 subs | 1 h 32 min368 subs | 4 h 07 min989 subs |
| Bode's GalaxyGalaxy | 50 min200 subs | 1 h 40 min400 subs | 4 h 33 min1,094 subs |
| Pinwheel GalaxyGalaxy | 3 h 24 min817 subs | 7 h 15 min1,739 subs | 21 h4,924 subs |
| Hercules ClusterGlobular cluster | 8 min30 subs | 11 min46 subs | 28 min111 subs |
| Dumbbell NebulaPlanetary nebula, dual-band | 26 min106 subs | 32 min129 subs | 52 min209 subs |
| Ring NebulaPlanetary nebula, dual-band | 10 min39 subs | 11 min44 subs | 16 min63 subs |
| Lagoon NebulaEmission nebula, dual-band | 25 min102 subs | 32 min127 subs | 54 min216 subs |
| Eagle NebulaEmission nebula, dual-band | 1 h 16 min303 subs | 1 h 39 min396 subs | 2 h 60 min719 subs |
| Omega NebulaEmission nebula, dual-band | 22 min88 subs | 27 min109 subs | 46 min183 subs |
| Trifid NebulaEmission nebula, dual-band | 55 min220 subs | 1 h 11 min284 subs | 2 h 07 min508 subs |
| Triangulum GalaxyGalaxy | 2 h 01 min486 subs | 4 h 14 min1,017 subs | 12 h2,850 subs |
| North America NebulaEmission nebula, dual-band | 1 h 45 min420 subs | 2 h 19 min555 subs | 4 h 15 min1,022 subs |
| Western Veil NebulaSupernova remnant, dual-band | 1 h 54 min456 subs | 2 h 31 min604 subs | 4 h 39 min1,116 subs |
| Eastern Veil NebulaSupernova remnant, dual-band | 1 h 37 min387 subs | 2 h 07 min510 subs | 3 h 54 min936 subs |
| Elephant's Trunk NebulaEmission nebula, dual-band | 2 h 53 min693 subs | 3 h 52 min928 subs | 7 h 15 min1,739 subs |
| Iris NebulaReflection nebula | 1 h 26 min346 subs | 2 h 58 min713 subs | 8 h 15 min1,981 subs |
| Pacman NebulaEmission nebula, dual-band | 2 h 04 min496 subs | 2 h 44 min658 subs | 5 h 05 min1,219 subs |
| Heart NebulaEmission nebula, dual-band | 3 h 25 min822 subs | 4 h 36 min1,104 subs | 8 h 40 min2,079 subs |
| Rosette NebulaEmission nebula, dual-band | 1 h 45 min420 subs | 2 h 19 min555 subs | 4 h 15 min1,022 subs |
| Horsehead NebulaEmission nebula, dual-band | 2 h 26 min586 subs | 3 h 15 min781 subs | 6 h 04 min1,456 subs |
| Flame NebulaEmission nebula, dual-band | 40 min160 subs | 51 min205 subs | 1 h 30 min360 subs |
| California NebulaEmission nebula, dual-band | 2 h 26 min586 subs | 3 h 15 min781 subs | 6 h 04 min1,456 subs |
| Helix NebulaPlanetary nebula, dual-band | 2 h 26 min586 subs | 3 h 15 min781 subs | 6 h 04 min1,456 subs |
| Double ClusterOpen cluster | 8 min30 subs | 8 min30 subs | 9 min35 subs |
| NGC 891Galaxy | 2 h 04 min495 subs | 4 h 18 min1,032 subs | 12 h2,886 subs |
| Sombrero GalaxyGalaxy | 39 min155 subs | 1 h 14 min295 subs | 3 h 15 min779 subs |
| Sunflower GalaxyGalaxy | 1 h 16 min305 subs | 2 h 35 min621 subs | 7 h 07 min1,710 subs |
All 170 targets have a page for the Dwarf 3.
Getting the most from the Dwarf 3
30 s and 60 s subs need EQ mode; 60 s is the recommended ceiling. Built-in filter wheel with Astro (UV/IR) and dual-band filters.
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 60 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.
Useful gear
Power, dew control and a stable tripod are what stop a long session early. Search links, not specific endorsements; check fit for your model.