How Many Subs

ZWO Seestar S30 Pro: how long to image deep-sky targets

The S30 optics upgraded to a quadruplet in front of an 8 MP IMX585. Same speed per pixel as the S30, four times the pixels, so you can crop hard.

SpecValue
Aperture30 mm
Focal length160 mm (f/5.3)
SensorSony IMX585, 3840 × 2160, 2.9 µm pixels
Pixel scale3.74″ per pixel
Field of view3.99° × 2.24° (239′ × 135′)
Sub exposures10 s, 20 s, 30 s, 60 s (default 10 s)
FiltersBuilt-in UV/IR-cut, dual-band (OIII 30 nm / Hα 20 nm) and dark filters on the telephoto camera. What the names mean.
In the calculator“UV/IR-cut (no light-pollution filter)” is the UV/IR-cut position; “dual-band” is the built-in dual-band (LP filter).
Read noise used1 e⁻
Where to buy the Seestar S30 ProZWO store DirectAmazon UKAmazon 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.

Weighing it against the others? The buying guide puts every scope on one table.

Popular targets

Total integration for a solid image, 10 s subs, recommended filter.
TargetBortle 4Bortle 6Bortle 8
Andromeda GalaxyGalaxy50 min300 subs1 h 41 min609 subs4 h 40 min1,678 subs
Orion NebulaEmission nebula, dual-band12 min73 subs15 min89 subs24 min146 subs
PleiadesReflection nebula1 h 30 min541 subs3 h 08 min1,127 subs8 h 45 min3,152 subs
Whirlpool GalaxyGalaxy35 min209 subs1 h 08 min407 subs3 h 02 min1,094 subs
Bode's GalaxyGalaxy37 min222 subs1 h 14 min444 subs3 h 22 min1,210 subs
Pinwheel GalaxyGalaxy2 h 31 min908 subs5 h 21 min1,927 subs15 h5,446 subs
Hercules ClusterGlobular cluster5 min31 subs8 min51 subs20 min123 subs
Dumbbell NebulaPlanetary nebula, dual-band20 min118 subs24 min144 subs39 min232 subs
Ring NebulaPlanetary nebula, dual-band7 min43 subs8 min49 subs11 min69 subs
Lagoon NebulaEmission nebula, dual-band19 min113 subs24 min142 subs40 min240 subs
Eagle NebulaEmission nebula, dual-band56 min338 subs1 h 14 min442 subs2 h 13 min798 subs
Omega NebulaEmission nebula, dual-band22 min133 subs27 min165 subs46 min277 subs
Trifid NebulaEmission nebula, dual-band41 min245 subs53 min317 subs1 h 34 min564 subs
Triangulum GalaxyGalaxy1 h 30 min541 subs3 h 08 min1,127 subs8 h 45 min3,152 subs
North America NebulaEmission nebula, dual-band1 h 18 min470 subs1 h 43 min619 subs3 h 09 min1,135 subs
Western Veil NebulaSupernova remnant, dual-band1 h 25 min510 subs1 h 52 min674 subs3 h 26 min1,239 subs
Eastern Veil NebulaSupernova remnant, dual-band1 h 12 min433 subs1 h 35 min569 subs2 h 53 min1,039 subs
Elephant's Trunk NebulaEmission nebula, dual-band2 h 09 min776 subs2 h 53 min1,036 subs5 h 22 min1,932 subs
Iris NebulaReflection nebula1 h 04 min384 subs2 h 12 min790 subs6 h 05 min2,191 subs
Pacman NebulaEmission nebula, dual-band1 h 32 min555 subs2 h 02 min734 subs3 h 46 min1,354 subs
Heart NebulaEmission nebula, dual-band2 h 33 min920 subs3 h 25 min1,232 subs6 h 25 min2,309 subs
Rosette NebulaEmission nebula, dual-band1 h 18 min470 subs1 h 43 min619 subs3 h 09 min1,135 subs
Horsehead NebulaEmission nebula, dual-band1 h 49 min656 subs2 h 25 min872 subs4 h 29 min1,617 subs
Flame NebulaEmission nebula, dual-band30 min179 subs38 min229 subs1 h 06 min399 subs
California NebulaEmission nebula, dual-band1 h 49 min656 subs2 h 25 min872 subs4 h 29 min1,617 subs
Helix NebulaPlanetary nebula, dual-band1 h 49 min656 subs2 h 25 min872 subs4 h 29 min1,617 subs
Double ClusterOpen cluster5 min30 subs5 min30 subs6 min39 subs
NGC 891Galaxy1 h 32 min550 subs3 h 10 min1,143 subs8 h 52 min3,192 subs
Sombrero GalaxyGalaxy29 min172 subs54 min327 subs2 h 24 min862 subs
Sunflower GalaxyGalaxy56 min339 subs1 h 55 min688 subs5 h 15 min1,891 subs

All 170 targets have a page for the Seestar S30 Pro.

Every target for the Seestar S30 Pro

Supernova remnants

Globular clusters

Open clusters

Emission nebulas

Star clouds

Planetary nebulas

Galaxies

Reflection nebulas

Getting the most from the Seestar S30 Pro

10, 20 and 30 s in Alt-Az; 60 s only in EQ mode, which needs the TH10 head. Built-in UV/IR-cut, dual-band (OIII 30 nm / Hα 20 nm) and dark filters on the telephoto camera.

Longer subs matter most under dark skies, where read noise rather than skyglow sets the floor. From a city the difference between 10 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.

Compare the Seestar S30 Pro

Useful gear

What actually fits this scope, checked against the maker's own pages: power, EQ mode, dew and carry.

Affiliate links: the retailer pays us a small commission and you pay the same price. These are search links to the named product, not endorsements of a particular listing; check the listing matches your model.

All Seestar S30 Pro accessories, and what to take on a cold night →