How long to image the M110 with the DwarfLab DWARF 3
From a Bortle 6 suburban sky, the DwarfLab DWARF 3 needs about 5 h 28 min (1,313 subs of 15 s) for a solid image of the M110. A quick look takes 1 h 22 min; a showpiece 22 h. Under a Bortle 3 rural sky the solid figure drops to 1 h 46 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 22% 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 | 21 min85 subs | 1 h 25 min340 subs | 5 h 39 min1,357 subs |
| Bortle 2Typical dark site | 23 min93 subs | 1 h 32 min369 subs | 6 h 09 min1,476 subs |
| Bortle 3Rural | 27 min107 subs | 1 h 46 min426 subs | 7 h 05 min1,702 subs |
| Bortle 4Rural / suburban transition | 35 min141 subs | 2 h 21 min563 subs | 9 h 22 min2,250 subs |
| Bortle 5Suburban | 49 min195 subs | 3 h 15 min780 subs | 13 h3,119 subs |
| Bortle 6Bright suburban | 1 h 22 min329 subs | 5 h 28 min1,313 subs | 22 h5,250 subs |
| Bortle 7Suburban / urban transition | 2 h 25 min582 subs | 9 h 42 min2,328 subs | 39 h9,311 subs |
| Bortle 8City | 4 h 04 min977 subs | 16 h3,905 subs | 65 h15,617 subs |
| Bortle 9Inner city | 7 h 34 min1,817 subs | 30 h7,266 subs | 120+ h29,064 subs |
Power and kit for this session
Allowing for slewing, focusing and rejected subs, that is about 7 h 07 min of run time. That is more than one night: over 2 nights, about 3 h 33 min each. The DWARF 3’s battery (rated about 5 h 30 min) should cover each night; a power bank still keeps the phone running the app alive. (Bortle 6, solid image; we allow 30% over the integration time.)
- USB-C PD power bank 20000mAh 18W18 W PD input and it runs while charging; needs a C-to-C cable for PD.
- 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 DWARF 3 →
How it frames
The M110 is 22′ × 11′ across. The DWARF 3 frames 2.93° × 1.65° at 2.75″ per pixel, so it fills 22% of the frame’s short side.
Longer subs
Auto mode caps subs at 15 s; 30 s and longer need EQ mode, and 60 s is the ceiling on the tele camera. Time for a solid image by sub length:
| Sub length | Bortle 3 | Bortle 5 | Bortle 7 |
|---|---|---|---|
| 15 s | 1 h 46 min426 subs | 3 h 15 min780 subs | 9 h 42 min2,328 subs |
| 30 s | 1 h 39 min198 subs | 3 h 07 min375 subs | 9 h 34 min1,149 subs |
| 60 s | 1 h 35 min95 subs | 3 h 03 min184 subs | 9 h 30 min571 subs |
Leave the dual-band filter out for the M110. It is a galaxy, and it shines right across the spectrum. A dual-band filter keeps two emission lines and throws the rest away, so most of the light you came for is being stopped along with the sky. From a Bortle 6 sky it would be roughly 10 times slower.
About the M110
Andromeda's larger, diffuse elliptical companion. Low surface brightness; it fades into the background in short stacks.
NGC 205 · Galaxy in Andromeda · magnitude 8.1 · 22′ × 11′ · best in Sep, Oct, Nov. 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 DwarfLab DWARF 3
Small pixels on a 35 mm f/4.3 lens give a sharper image than its aperture suggests, and EQ mode with 60 s subs makes it the read-noise winner in dark skies.
Auto mode caps subs at 15 s; 30 s and longer need EQ mode, and 60 s is the ceiling on the tele camera. Three built-in filters: VIS, Astro (430 to 690 nm) and dual-band Hα 656 nm / OIII 501 nm.
Longer subs matter most under dark skies, where read noise rather than skyglow sets the floor. From a city the difference between 15 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.
Have an image of the M110 from a DWARF 3? Email it with your total time and sky to [email protected] and it goes here, credited.
Same target, other telescopes
- M110 with the ZWO Seestar S50: 3 h 46 min from Bortle 6
- M110 with the ZWO Seestar S50 Pro: 4 h 08 min from Bortle 6
- M110 with the ZWO Seestar S30: 3 h 58 min from Bortle 6
- M110 with the ZWO Seestar S30 Pro: 4 h 23 min from Bortle 6
- M110 with the DwarfLab DWARF mini: 3 h 45 min from Bortle 6
- M110 with the DwarfLab Draco: 3 h 06 min from Bortle 6
- M110 with the DwarfLab DWARF II: 13 h from Bortle 6
- M110 with the Vaonis Vespera II: 3 h 46 min from Bortle 6
- M110 with the Vaonis Vespera Pro: 8 h 28 min from Bortle 6
- M110 with the Vaonis Vespera 3: 3 h 36 min from Bortle 6
- M110 with the Vaonis Vespera Pro 2: 8 h 04 min from Bortle 6
- M110 with the Unistellar eQuinox 2: 3 h 28 min from Bortle 6
- M110 with the Unistellar Odyssey: 16 h from Bortle 6
- M110 with the Celestron Origin: 1 h from Bortle 6
- M110 with the Celestron Origin Mark II: 1 h 22 min from Bortle 6