How long to image the M88 with the Unistellar eQuinox 2
From a Bortle 6 suburban sky, the Unistellar eQuinox 2 needs about 1 h 39 min (1,479 subs of 4 s) for a solid image of the M88. A quick look takes 25 min; a showpiece 6 h 34 min. Under a Bortle 3 rural sky the solid figure drops to 58 min. At Bortle 6 the limit is a mix of skyglow and read noise. In this scope's field it fills 20% 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 | 13 min203 subs | 54 min810 subs | 3 h 36 min3,238 subs |
| Bortle 2Typical dark site | 14 min208 subs | 55 min830 subs | 3 h 41 min3,320 subs |
| Bortle 3Rural | 14 min218 subs | 58 min869 subs | 3 h 52 min3,476 subs |
| Bortle 4Rural / suburban transition | 16 min241 subs | 1 h 04 min964 subs | 4 h 17 min3,853 subs |
| Bortle 5Suburban | 19 min279 subs | 1 h 14 min1,113 subs | 4 h 57 min4,450 subs |
| Bortle 6Bright suburban | 25 min370 subs | 1 h 39 min1,479 subs | 6 h 34 min5,916 subs |
| Bortle 7Suburban / urban transition | 36 min545 subs | 2 h 25 min2,178 subs | 9 h 41 min8,710 subs |
| Bortle 8City | 54 min816 subs | 3 h 37 min3,262 subs | 14 h13,048 subs |
| Bortle 9Inner city | 1 h 33 min1,394 subs | 6 h 12 min5,575 subs | 25 h22,298 subs |
Power and kit for this session
Allowing for slewing, focusing and rejected subs, that is about 2 h 08 min of run time. The eQuinox 2’s battery (rated about 11 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-C power bank 20000mAh 5V 2AUnistellar asks for a 5 V 2 A output; PD is not needed.
- red LED head torchRed light keeps your night vision; white light costs you twenty minutes of dark adaptation every 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 eQuinox 2 →
How it frames
The M88 is 7′ × 4′ across. The eQuinox 2 frames 0.76° × 0.57° at 1.33″ per pixel, so it fills 20% of the frame’s short side.
About the M88
A tilted spiral in the Virgo cluster with tightly wound arms.
NGC 4501 · Galaxy in Coma Berenices · magnitude 9.6 · 7′ × 4′ · 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 eQuinox 2
A 114 mm Newtonian with five times the light grasp of a 50 mm refractor. Fixed 4 s subs put it in read-noise territory under dark skies, but the aperture carries it. The published field is 45.6′ × 34.2′, a crop of the sensor.
Fixed 4 s subs in Enhanced Vision; they cannot be changed. No built-in filter. Unistellar sells only a solar filter and says a third-party filter is at your own risk and voids the warranty.
The eQuinox 2 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 M88 from a eQuinox 2? Email it with your total time and sky to [email protected] and it goes here, credited.
Same target, other telescopes
- M88 with the ZWO Seestar S50: 1 h 50 min from Bortle 6
- M88 with the ZWO Seestar S50 Pro: 2 h from Bortle 6
- M88 with the ZWO Seestar S30: 1 h 55 min from Bortle 6
- M88 with the ZWO Seestar S30 Pro: 2 h 07 min from Bortle 6
- M88 with the DwarfLab DWARF 3: 2 h 40 min from Bortle 6
- M88 with the DwarfLab DWARF mini: 1 h 49 min from Bortle 6
- M88 with the DwarfLab Draco: 1 h 30 min from Bortle 6
- M88 with the DwarfLab DWARF II: 6 h 13 min from Bortle 6
- M88 with the Vaonis Vespera II: 1 h 50 min from Bortle 6
- M88 with the Vaonis Vespera Pro: 4 h 05 min from Bortle 6
- M88 with the Vaonis Vespera 3: 1 h 45 min from Bortle 6
- M88 with the Vaonis Vespera Pro 2: 3 h 54 min from Bortle 6
- M88 with the Unistellar Odyssey: 7 h 34 min from Bortle 6
- M88 with the Celestron Origin: 29 min from Bortle 6
- M88 with the Celestron Origin Mark II: 40 min from Bortle 6