Is the Seestar S50 faster than the DWARF 3?

From a Bortle 6 sky the Seestar S50 is 1.3× faster on the 30 most popular deep-sky targets; from Bortle 3 the Seestar S50 is 1.2× faster.

Which is better for small targets like planetary nebulae?

The Seestar S50, with its finer pixel scale of 2.39″ per pixel.

Seestar S50 vs DWARF 3: which is faster for deep-sky imaging?

ZWO Seestar S50 against DwarfLab DWARF 3, 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 S50 is 1.3× 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 S50 is 1.2× faster.

Field of view. The DWARF 3 shows 2.93° × 1.65° against 1.28° × 0.72°, so big targets such as the Andromeda Galaxy, the North America Nebula and the Pleiades fit with room to spare where the Seestar S50 needs a mosaic or a tight crop.

Detail. The Seestar S50 samples at 2.39″ per pixel against 2.75″, so it pulls finer structure from small targets: planetary nebulae, globular cores, galaxy arms.

Subs and dark skies. Both top out at 60 s subs, so neither has an edge at read-noise-limited dark sites.

Filters. Both carry a dual-band filter, which is what makes emission nebulae practical from a lit sky.

Specifications side by side

Spec	Seestar S50	DWARF 3
Aperture	50 mm	35 mm
Focal length	250 mm (f/5.0)	150 mm (f/4.3)
Sensor	Sony IMX462, 2.1 MP	Sony IMX678, 8.3 MP
Pixel size	2.9 µm	2 µm
Pixel scale	2.39″/px	2.75″/px
Field of view	1.28° × 0.72°	2.93° × 1.65°
Sub exposures	10 s, 20 s, 30 s, 60 s	15 s, 30 s, 60 s
Dual-band filter	Built in (LP filter)	Built in (Dual-band)
“No filter” position	UV/IR-cut	Astro
Read noise used	1 e⁻	0.6 e⁻

Timed on the same targets

Suburban sky (Bortle 6)

Total integration for a solid image from a Bortle 6 sky, default subs, recommended filter for each scope.
Target	Seestar S50	DWARF 3	Faster
Andromeda GalaxyGalaxy	1 h 27 min525 subs	2 h 07 min509 subs	Seestar S50 1.5×
Orion NebulaEmission nebula	12 min75 subs	16 min66 subs	Seestar S50 1.3×
North America NebulaEmission nebula	1 h 25 min512 subs	1 h 46 min424 subs	Seestar S50 1.2×
Pinwheel GalaxyGalaxy	4 h 37 min1,661 subs	6 h 41 min1,604 subs	Seestar S50 1.4×
Ring NebulaPlanetary nebula	7 min42 subs	10 min39 subs	Seestar S50 1.4×
Western Veil NebulaSupernova remnant	1 h 33 min557 subs	1 h 55 min460 subs	Seestar S50 1.2×
Hercules ClusterGlobular cluster	7 min44 subs	11 min44 subs	Seestar S50 1.5×
PleiadesReflection nebula	2 h 42 min971 subs	3 h 55 min939 subs	Seestar S50 1.5×

Rural sky (Bortle 3)

Total integration for a solid image from a Bortle 3 sky, default subs, recommended filter for each scope.
Target	Seestar S50	DWARF 3	Faster
Andromeda GalaxyGalaxy	34 min204 subs	44 min178 subs	Seestar S50 1.3×
Orion NebulaEmission nebula	10 min58 subs	12 min48 subs	Seestar S50 1.2×
North America NebulaEmission nebula	59 min357 subs	1 h 06 min264 subs	Seestar S50 1.1×
Pinwheel GalaxyGalaxy	1 h 40 min602 subs	2 h 08 min514 subs	Seestar S50 1.3×
Ring NebulaPlanetary nebula	6 min36 subs	8 min33 subs	Seestar S50 1.4×
Western Veil NebulaSupernova remnant	1 h 04 min387 subs	1 h 11 min285 subs	Seestar S50 1.1×
Hercules ClusterGlobular cluster	5 min30 subs	8 min30 subs	Seestar S50 1.5×
PleiadesReflection nebula	1 h362 subs	1 h 18 min312 subs	Seestar S50 1.3×

Try the Seestar S50 in the calculator Try the DWARF 3

About the ZWO Seestar S50

The scope that made smart astrophotography mainstream. 50 mm triplet, 2 MP sensor, dual-band filter on a wheel. Alt-Az stacking at 10 s, EQ mode unlocks 60 s. Out of production since 2026 and replaced by the S50 Pro, but there are a great many in use.

Where to buy the Seestar S50ZWO store Direct Amazon UK Amazon USThe ZWO store link is a plain link; the others are affiliate links. As an Amazon Associate I earn from qualifying purchases, at no cost to you.

About the DwarfLab DWARF 3

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.

Where to buy the DWARF 3DwarfLab store UK DwarfLab store US Amazon UK Amazon USThe DwarfLab store link is a plain link; the others are affiliate links. As an Amazon Associate I earn from qualifying purchases, at no cost to you.

Other comparisons

All comparisons · Buying guide · Seestar S50 page · DWARF 3 page