How long to image the M77 with the DwarfLab DWARF II
From a Bortle 6 suburban sky, the DwarfLab DWARF II needs about 1 h 41 min (404 subs of 15 s) for a solid image of the M77. A quick look takes 25 min; a showpiece 6 h 43 min. Under a Bortle 3 rural sky the solid figure drops to 56 min. At Bortle 6 the limit is a mix of skyglow and read noise. In this scope's field it fills 7% 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 min52 subs | 52 min207 subs | 3 h 27 min828 subs |
| Bortle 2Typical dark site | 13 min54 subs | 53 min213 subs | 3 h 33 min852 subs |
| Bortle 3Rural | 14 min57 subs | 56 min225 subs | 3 h 44 min897 subs |
| Bortle 4Rural / suburban transition | 16 min63 subs | 1 h 03 min252 subs | 4 h 12 min1,008 subs |
| Bortle 5Suburban | 18 min74 subs | 1 h 14 min296 subs | 4 h 56 min1,183 subs |
| Bortle 6Bright suburban | 25 min101 subs | 1 h 41 min404 subs | 6 h 43 min1,613 subs |
| Bortle 7Suburban / urban transition | 38 min152 subs | 2 h 32 min608 subs | 10 h2,432 subs |
| Bortle 8City | 58 min232 subs | 3 h 51 min926 subs | 15 h3,704 subs |
| Bortle 9Inner city | 1 h 40 min401 subs | 6 h 41 min1,604 subs | 27 h6,416 subs |
Power and kit for this session
Allowing for slewing, focusing and rejected subs, that is about 2 h 11 min of run time. The DWARF II’s battery is rated at about 3 h, less near freezing, so the session needs an external power bank. (Bortle 6, solid image; we allow 30% over the integration time, and 30% off the battery for a November night.)
- USB-C PD power bank 10000mAh 18W18 W PD input; runs while charging.
- red LED head torchRed light keeps your night vision; white light costs you twenty minutes of dark adaptation every time.
- hand warmers long lastingAir-activated packs give hours of heat for the person; winter nights are long and you spend most of them standing still.
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 II →
How it frames
The M77 is 7′ × 6′ across. The DWARF II frames 3.19° × 1.79° at 2.99″ per pixel, so it fills 7% of the frame’s short side.
About the M77
A Seyfert galaxy with a blazing core and faint outer arms. The nucleus is easy; the arms are not.
NGC 1068 · Galaxy in Cetus · magnitude 8.9 · 7′ × 6′ · best in Oct, Nov, Dec. 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 II
The original pocket scope. 24 mm aperture and tiny 1.45 µm pixels mean it is slow per pixel, so bin or downsample and be patient.
15 s is the hard maximum in any mode; DwarfLab recommends EQ mode at 15 s. Two built-in filters, VIS and Astro (IR-pass); no dual-band. The optional UHC filter is no longer sold.
The DWARF II uses fixed 15 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 M77 from a DWARF II? Email it with your total time and sky to [email protected] and it goes here, credited.
Same target, other telescopes
- M77 with the ZWO Seestar S50: 30 min from Bortle 6
- M77 with the ZWO Seestar S50 Pro: 33 min from Bortle 6
- M77 with the ZWO Seestar S30: 32 min from Bortle 6
- M77 with the ZWO Seestar S30 Pro: 35 min from Bortle 6
- M77 with the DwarfLab DWARF 3: 44 min from Bortle 6
- M77 with the DwarfLab DWARF mini: 30 min from Bortle 6
- M77 with the DwarfLab Draco: 25 min from Bortle 6
- M77 with the Vaonis Vespera II: 30 min from Bortle 6
- M77 with the Vaonis Vespera Pro: 1 h 07 min from Bortle 6
- M77 with the Vaonis Vespera 3: 29 min from Bortle 6
- M77 with the Vaonis Vespera Pro 2: 1 h 04 min from Bortle 6
- M77 with the Unistellar eQuinox 2: 26 min from Bortle 6
- M77 with the Unistellar Odyssey: 1 h 59 min from Bortle 6
- M77 with the Celestron Origin: 8 min from Bortle 6
- M77 with the Celestron Origin Mark II: 11 min from Bortle 6