Seestar S30 vs DWARF II: which is faster for deep-sky imaging?
ZWO Seestar S30 against DwarfLab DWARF II, on the same targets from the same skies, using the same photon-budget model as the rest of the site. Times are for a solid image; the calculator gives quick-look and showpiece figures too.
Speed. Across the 30 most popular targets from a suburban Bortle 6 sky, the Seestar S30 is 4× faster (geometric mean of the solid-image times, each scope on its recommended filter and default subs). From a rural Bortle 3 sky the Seestar S30 is 3× faster.
Field of view. The DWARF II shows 3.19° × 1.79° against 2.13° × 1.20°, so big targets such as the Andromeda Galaxy, the North America Nebula and the Pleiades fit with room to spare where the Seestar S30 needs a mosaic or a tight crop.
Detail. The DWARF II samples at 2.99″ per pixel against 3.99″, so it pulls finer structure from small targets: planetary nebulae, globular cores, galaxy arms.
Subs and dark skies. The Seestar S30 goes up to 60 s subs in EQ mode, the DWARF II tops out at 15 s. That matters little from a city, where skyglow sets the floor, and a lot from a dark site, where read noise does.
Filters. The Seestar S30 has a dual-band filter built in; the DWARF II does not, which costs it heavily on emission nebulae from any suburban sky.
Specifications side by side
| Spec | Seestar S30 | DWARF II |
|---|---|---|
| Aperture | 30 mm | 24 mm |
| Focal length | 150 mm (f/5.0) | 100 mm (f/4.2) |
| Sensor | Sony IMX662, 2.1 MP | Sony IMX415, 8.3 MP |
| Pixel size | 2.9 µm | 1.45 µm |
| Pixel scale | 3.99″/px | 2.99″/px |
| Field of view | 2.13° × 1.20° | 3.19° × 1.79° |
| Sub exposures | 10 s, 20 s, 30 s, 60 s | 15 s |
| Dual-band filter | Built in (LP filter) | None |
| “No filter” position | UV/IR-cut | Astro |
| Read noise used | 1.2 e⁻ | 1.2 e⁻ |
Timed on the same targets
Suburban sky (Bortle 6)
| Target | Seestar S30 | DWARF II | Faster |
|---|---|---|---|
| Andromeda GalaxyGalaxy | 1 h 32 min552 subs | 4 h 59 min1,198 subs | Seestar S30 3× |
| Orion NebulaEmission nebula | 14 min84 subs | 57 min228 subs | Seestar S30 4× |
| North America NebulaEmission nebula | 1 h 39 min597 subs | 7 h 45 min1,860 subs | Seestar S30 5× |
| Pinwheel GalaxyGalaxy | 4 h 51 min1,748 subs | 16 h3,817 subs | Seestar S30 3× |
| Ring NebulaPlanetary nebula | 7 min45 subs | 25 min101 subs | Seestar S30 3× |
| Western Veil NebulaSupernova remnant | 1 h 48 min651 subs | 8 h 29 min2,035 subs | Seestar S30 5× |
| Hercules ClusterGlobular cluster | 8 min46 subs | 24 min97 subs | Seestar S30 3× |
| PleiadesReflection nebula | 2 h 50 min1,022 subs | 9 h 16 min2,225 subs | Seestar S30 3× |
Rural sky (Bortle 3)
| Target | Seestar S30 | DWARF II | Faster |
|---|---|---|---|
| Andromeda GalaxyGalaxy | 38 min231 subs | 2 h 31 min603 subs | Seestar S30 4× |
| Orion NebulaEmission nebula | 11 min67 subs | 31 min126 subs | Seestar S30 2.8× |
| North America NebulaEmission nebula | 1 h 14 min442 subs | 3 h 50 min922 subs | Seestar S30 3× |
| Pinwheel GalaxyGalaxy | 1 h 55 min689 subs | 7 h 44 min1,856 subs | Seestar S30 4× |
| Ring NebulaPlanetary nebula | 6 min39 subs | 16 min64 subs | Seestar S30 2.5× |
| Western Veil NebulaSupernova remnant | 1 h 20 min481 subs | 4 h 11 min1,006 subs | Seestar S30 3× |
| Hercules ClusterGlobular cluster | 5 min30 subs | 14 min57 subs | Seestar S30 2.8× |
| PleiadesReflection nebula | 1 h 09 min412 subs | 4 h 34 min1,097 subs | Seestar S30 4× |
Try the Seestar S30 in the calculator Try the DWARF II
About the ZWO Seestar S30
Wider and lighter than the S50 with the same 2.9 µm pixels, so its per-pixel speed on extended targets is close despite the smaller aperture. Ideal for big nebulae.
About the DwarfLab DWARF II
The original pocket scope. 24 mm aperture and tiny 1.45 µm pixels mean it is slow per pixel, so bin or downsample and be patient.
Other comparisons
Seestar S30
- Seestar S50 vs Seestar S30
- Seestar S50 Pro vs Seestar S30
- Seestar S30 vs Seestar S30 Pro
- Seestar S30 vs DWARF 3
- Seestar S30 vs DWARF mini
- Seestar S30 vs Draco
- Seestar S30 vs DWARF II
- Seestar S30 vs Vespera II
- Seestar S30 vs Vespera Pro
- Seestar S30 vs Vespera 3
- Seestar S30 vs Vespera Pro 2
- Seestar S30 vs eQuinox 2
- Seestar S30 vs Odyssey
- Seestar S30 vs Origin
- Seestar S30 vs Origin Mark II
DWARF II
- Seestar S50 vs DWARF II
- Seestar S50 Pro vs DWARF II
- Seestar S30 vs DWARF II
- Seestar S30 Pro vs DWARF II
- DWARF 3 vs DWARF II
- DWARF mini vs DWARF II
- Draco vs DWARF II
- DWARF II vs Vespera II
- DWARF II vs Vespera Pro
- DWARF II vs Vespera 3
- DWARF II vs Vespera Pro 2
- DWARF II vs eQuinox 2
- DWARF II vs Odyssey
- DWARF II vs Origin
- DWARF II vs Origin Mark II
All comparisons · Buying guide · Seestar S30 page · DWARF II page