How long to image the M59 with the Unistellar Odyssey
From a Bortle 6 suburban sky, the Unistellar Odyssey needs about 3 h 13 min (2,899 subs of 4 s) for a solid image of the M59. A quick look takes 48 min; a showpiece 13 h. Under a Bortle 3 rural sky the solid figure drops to 2 h 13 min. At Bortle 6 the limit is a mix of skyglow and read noise. In this scope's field it fills 15% of the frame’s short side.
| Sky | Quick lookTarget obvious, still noisy | SolidClean enough to share | ShowpieceSmooth faint detail, print-worthy |
|---|---|---|---|
| Bortle 1Excellent dark site | 32 min475 subs | 2 h 07 min1,900 subs | 8 h 26 min7,598 subs |
| Bortle 2Typical dark site | 32 min483 subs | 2 h 09 min1,931 subs | 8 h 35 min7,721 subs |
| Bortle 3Rural | 33 min498 subs | 2 h 13 min1,989 subs | 8 h 50 min7,953 subs |
| Bortle 4Rural / suburban transition | 35 min533 subs | 2 h 22 min2,129 subs | 9 h 28 min8,516 subs |
| Bortle 5Suburban | 39 min588 subs | 2 h 37 min2,352 subs | 10 h9,407 subs |
| Bortle 6Bright suburban | 48 min725 subs | 3 h 13 min2,899 subs | 13 h11,595 subs |
| Bortle 7Suburban / urban transition | 1 h 06 min986 subs | 4 h 23 min3,941 subs | 18 h15,764 subs |
| Bortle 8City | 1 h 33 min1,390 subs | 6 h 11 min5,560 subs | 25 h22,237 subs |
| Bortle 9Inner city | 2 h 30 min2,253 subs | 10 h9,011 subs | 40 h36,042 subs |
Power and kit for this session
Allowing for slewing, focusing and rejected subs, that is about 4 h 11 min of run time. The Odyssey’s battery (rated about 5 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.)
- USB power bank 20000mAh 5V 2.4AUnistellar says plain 5 V 2.4 A and warns against fast or adaptive chargers.
- red LED head torchRed light keeps your night vision; white light costs you twenty minutes of dark adaptation every time.
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Everything that fits the Odyssey →
How it frames
The M59 is 5′ × 3.5′ across. The Odyssey frames 0.75° × 0.56° at 0.93″ per pixel, so it fills 15% of the frame’s short side.
About the M59
An elliptical galaxy in Virgo, close to M60. A smudge, but a bright one.
NGC 4621 · Galaxy in Virgo · magnitude 9.6 · 5′ × 3.5′ · 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 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.
Fixed 4 s subs in Enhanced Vision; they cannot be changed. No filter option; Unistellar says third-party filters cannot be fitted to the Odyssey.
The Odyssey uses fixed 4 s subs, so the only levers you have are the sky you shoot from, the filter, and total time.
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.
Have an image of the M59 from a Odyssey? Email it with your total time and sky to [email protected] and it goes here, credited.
Same target, other telescopes
- M59 with the ZWO Seestar S50: 48 min from Bortle 6
- M59 with the ZWO Seestar S50 Pro: 53 min from Bortle 6
- M59 with the ZWO Seestar S30: 50 min from Bortle 6
- M59 with the ZWO Seestar S30 Pro: 56 min from Bortle 6
- M59 with the DwarfLab DWARF 3: 1 h 10 min from Bortle 6
- M59 with the DwarfLab DWARF mini: 48 min from Bortle 6
- M59 with the DwarfLab Draco: 40 min from Bortle 6
- M59 with the DwarfLab DWARF II: 2 h 42 min from Bortle 6
- M59 with the Vaonis Vespera II: 48 min from Bortle 6
- M59 with the Vaonis Vespera Pro: 1 h 47 min from Bortle 6
- M59 with the Vaonis Vespera 3: 46 min from Bortle 6
- M59 with the Vaonis Vespera Pro 2: 1 h 42 min from Bortle 6
- M59 with the Unistellar eQuinox 2: 42 min from Bortle 6
- M59 with the Celestron Origin: 13 min from Bortle 6
- M59 with the Celestron Origin Mark II: 18 min from Bortle 6