Is the Vespera II faster than the Odyssey?

From a Bortle 6 sky the Vespera II is 4× faster on the 30 most popular deep-sky targets; from Bortle 3 the Vespera II is 7× faster.

Which is better for small targets like planetary nebulae?

The Odyssey, with its finer pixel scale of 0.93″ per pixel.

Vespera II vs Odyssey: which is faster for deep-sky imaging?

Vaonis Vespera II against Unistellar Odyssey, 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 Vespera II 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 Vespera II is 7× faster.

Field of view. The Vespera II shows 2.55° × 1.44° against 0.75° × 0.56°, so big targets such as the Andromeda Galaxy, the North America Nebula and the Pleiades fit with room to spare where the Odyssey needs a mosaic or a tight crop.

Detail. The Odyssey samples at 0.93″ per pixel against 2.39″, so it pulls finer structure from small targets: planetary nebulae, globular cores, galaxy arms.

Subs and dark skies. The Vespera II goes up to 30 s subs in Expert Mode, the Odyssey tops out at 4 s. That matters little from a city, where skyglow sets the floor, and a lot from a dark site, where read noise does.

Filters. Neither has a built-in dual-band filter, so emission nebulae from a lit sky are slow going on both.

Specifications side by side

Spec	Vespera II	Odyssey
Aperture	50 mm	85 mm
Focal length	250 mm (f/5.0)	320 mm (f/3.8)
Sensor	Sony IMX585, 8.3 MP	IMX415-class, 1.45 µm (Unistellar does not name it), 6.2 MP
Pixel size	2.9 µm	1.45 µm
Pixel scale	2.39″/px	0.93″/px
Field of view	2.55° × 1.44°	0.75° × 0.56°
Sub exposures	10 s, 20 s, 30 s	4 s
Dual-band filter	Clip-on option (Dual Band filter)	None
“No filter” position	No filter	No filter
Read noise used	1 e⁻	1.2 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	Vespera II	Odyssey	Faster
Andromeda GalaxyGalaxy	1 h 27 min525 subs	6 h 07 min5,505 subs	Vespera II 4×
Orion NebulaEmission nebula	17 min103 subs	1 h 08 min1,016 subs	Vespera II 4×
North America NebulaEmission nebula	2 h 15 min813 subs	9 h 33 min8,594 subs	Vespera II 4×
Pinwheel GalaxyGalaxy	4 h 37 min1,661 subs	20 h17,741 subs	Vespera II 4×
Ring NebulaPlanetary nebula	8 min47 subs	28 min422 subs	Vespera II 4×
Western Veil NebulaSupernova remnant	2 h 28 min889 subs	10 h9,406 subs	Vespera II 4×
Hercules ClusterGlobular cluster	7 min44 subs	28 min419 subs	Vespera II 4×
PleiadesReflection nebula	2 h 42 min971 subs	11 h10,297 subs	Vespera II 4×

Rural sky (Bortle 3)

Total integration for a solid image from a Bortle 3 sky, default subs, recommended filter for each scope.
Target	Vespera II	Odyssey	Faster
Andromeda GalaxyGalaxy	34 min204 subs	4 h 05 min3,683 subs	Vespera II 7×
Orion NebulaEmission nebula	8 min47 subs	47 min701 subs	Vespera II 6×
North America NebulaEmission nebula	51 min306 subs	6 h 21 min5,721 subs	Vespera II 7×
Pinwheel GalaxyGalaxy	1 h 40 min602 subs	13 h11,739 subs	Vespera II 8×
Ring NebulaPlanetary nebula	5 min30 subs	21 min309 subs	Vespera II 4×
Western Veil NebulaSupernova remnant	55 min333 subs	6 h 57 min6,257 subs	Vespera II 8×
Hercules ClusterGlobular cluster	5 min30 subs	20 min297 subs	Vespera II 4×
PleiadesReflection nebula	1 h362 subs	7 h 36 min6,843 subs	Vespera II 8×

Try the Vespera II in the calculator Try the Odyssey

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.

Where to buy the Vespera IIVaonis store Direct Amazon UK Amazon 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.

About the Unistellar Odyssey

Unistellar’s compact 85 mm with autofocus and tiny pixels. Sharp, but the fine sampling costs time on faint extended targets. The Odyssey Pro is the same telescope with an eyepiece added, so these figures apply to both.

Where to buy the OdysseyAmazon UK Unistellar UK Amazon US Unistellar USAffiliate links: As an Amazon Associate I earn from qualifying purchases, at no cost to you.

Other comparisons

All comparisons · Buying guide · Vespera II page · Odyssey page