How long to image the Southern Pinwheel with the Vaonis Vespera II

From a Bortle 6 suburban sky, the Vaonis Vespera II needs about 47 min (281 subs of 10 s) for a solid image of the Southern Pinwheel. A quick look takes 12 min; a showpiece 3 h 07 min. Under a Bortle 3 rural sky the solid figure drops to 19 min. At Bortle 6 the limit is skyglow, so a darker site or a filter helps more than longer subs. In this scope's field it fills 15% of the frame’s short side.

Southern Pinwheel with the Vaonis Vespera II: 10 s subs.
SkyQuick lookTarget obvious, still noisySolidClean enough to shareShowpieceSmooth faint detail, print-worthy
Bortle 1Excellent dark site4 min26 subs17 min101 subs1 h 07 min401 subs
Bortle 2Typical dark site4 min27 subs18 min106 subs1 h 10 min423 subs
Bortle 3Rural5 min30 subs19 min117 subs1 h 17 min465 subs
Bortle 4Rural / suburban transition6 min36 subs24 min142 subs1 h 34 min566 subs
Bortle 5Suburban8 min46 subs30 min182 subs2 h 01 min727 subs
Bortle 6Bright suburban12 min71 subs47 min281 subs3 h 07 min1,122 subs
Bortle 7Suburban / urban transition20 min118 subs1 h 18 min469 subs5 h 12 min1,875 subs
Bortle 8City32 min191 subs2 h 07 min761 subs8 h 27 min3,044 subs
Bortle 9Inner city58 min346 subs3 h 51 min1,384 subs15 h5,536 subs

Adjust in the calculator

Power and kit for this session

Allowing for slewing, focusing and rejected subs, that is about 1 h 01 min of run time. The Vespera II’s battery (rated about 4 h) should cover it; a power bank still keeps the phone running the app alive. (Bortle 6, solid image; we allow 30% over the integration time.)

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.

Everything that fits the Vespera II →

How it frames

The Southern Pinwheel is 13′ × 12′ across. The Vespera II frames 2.55° × 1.44° at 2.39″ per pixel, so it fills 15% of the frame’s short side.

Longer subs

10 s subs by default; Expert Mode manual targets allow 1 to 30 s. Alt-azimuth only, no EQ mode. Time for a solid image by sub length:

Sub lengthBortle 3Bortle 5Bortle 7
10 s19 min117 subs30 min182 subs1 h 18 min469 subs
20 s17 min51 subs28 min84 subs1 h 16 min227 subs
30 s16 min32 subs27 min54 subs1 h 15 min150 subs

About the Southern Pinwheel

A bright barred spiral, superb from the southern hemisphere and a low-altitude struggle from northern Europe.

M83, NGC 5236 · Galaxy in Hydra · magnitude 7.6 · 13′ × 12′ · best in Mar, Apr, May. Reachable from mid-northern latitudes (UK, northern US, central Europe) and from the south.

Galaxies are broadband targets: their light is mostly starlight spread across the spectrum, so a dual-band filter throws most of it away and makes things slower, not faster. Shoot without a filter (or with a plain UV/IR cut) and rely on total time and a dark sky. The core of a galaxy is usually many times brighter than its outer disc, so a short stack shows the nucleus long before the arms; the figures here are for the arms and disc, not the core.

Field rotation in Alt-Az mode crops the edges of the stack over a long session, so on a big galaxy re-centre now and then or use EQ mode where your scope supports it.

About the Vaonis Vespera II

A 50 mm quadruplet on an 8 MP sensor with Vaonis’s mosaic mode for wide fields. Same optics class as the Seestar S50, four times the pixels.

10 s subs by default; Expert Mode manual targets allow 1 to 30 s. Alt-azimuth only, no EQ mode. Optional clip-on Vaonis filters: dual-band, light-pollution (CLS) and solar; the app detects which is fitted.

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 30 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.

Where to buy the Vespera IIVaonis store DirectAmazon UKAmazon USThe Vaonis 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.
Imaged the Southern Pinwheel with your Vespera II? Did the solid figure match?Anonymous, one tap. It is how the model gets calibrated.

Have an image of the Southern Pinwheel from a Vespera II? Email it with your total time and sky to [email protected] and it goes here, credited.

Same target, other telescopes

All telescopes for the Southern Pinwheel · All targets for the Vespera II