How long to image the Whale Galaxy with the DwarfLab DWARF II
From a Bortle 6 suburban sky, the DwarfLab DWARF II needs about 3 h 06 min (743 subs of 15 s) for a solid image of the Whale Galaxy. A quick look takes 46 min; a showpiece 12 h. Under a Bortle 3 rural sky the solid figure drops to 1 h 35 min. At Bortle 6 the limit is a mix of skyglow and read noise. In this scope's field it fills 14% 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 | 22 min87 subs | 1 h 26 min346 subs | 5 h 46 min1,383 subs |
| Bortle 2Typical dark site | 22 min90 subs | 1 h 29 min358 subs | 5 h 58 min1,432 subs |
| Bortle 3Rural | 24 min96 subs | 1 h 35 min381 subs | 6 h 21 min1,524 subs |
| Bortle 4Rural / suburban transition | 27 min110 subs | 1 h 49 min437 subs | 7 h 17 min1,748 subs |
| Bortle 5Suburban | 33 min132 subs | 2 h 11 min526 subs | 8 h 45 min2,102 subs |
| Bortle 6Bright suburban | 46 min186 subs | 3 h 06 min743 subs | 12 h2,971 subs |
| Bortle 7Suburban / urban transition | 1 h 12 min290 subs | 4 h 49 min1,157 subs | 19 h4,628 subs |
| Bortle 8City | 1 h 52 min450 subs | 7 h 30 min1,800 subs | 30 h7,200 subs |
| Bortle 9Inner city | 3 h 18 min793 subs | 13 h3,172 subs | 53 h12,686 subs |
Power and kit for this session
Allowing for slewing, focusing and rejected subs, that is about 4 h 01 min of run time. The DWARF II’s battery is rated at about 3 h, so the session needs an external power bank. (Bortle 6, solid image; we allow 30% over the integration time.)
- 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.
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Everything that fits the DWARF II →
How it frames
The Whale Galaxy is 15.5′ × 2.7′ across. The DWARF II frames 3.19° × 1.79° at 2.99″ per pixel, so it fills 14% of the frame’s short side.
About the Whale Galaxy
A distorted edge-on galaxy with a small companion on its back, and the Hockey Stick (NGC 4656) in the same wide field.
NGC 4631, Caldwell 32 · Galaxy in Canes Venatici · magnitude 9.2 · 15.5′ × 2.7′ · 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 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 Whale Galaxy from a DWARF II? Email it with your total time and sky to [email protected] and it goes here, credited.
Same target, other telescopes
- Whale Galaxy with the ZWO Seestar S50: 55 min from Bortle 6
- Whale Galaxy with the ZWO Seestar S50 Pro: 1 h from Bortle 6
- Whale Galaxy with the ZWO Seestar S30: 57 min from Bortle 6
- Whale Galaxy with the ZWO Seestar S30 Pro: 1 h 03 min from Bortle 6
- Whale Galaxy with the DwarfLab DWARF 3: 1 h 19 min from Bortle 6
- Whale Galaxy with the DwarfLab DWARF mini: 54 min from Bortle 6
- Whale Galaxy with the DwarfLab Draco: 45 min from Bortle 6
- Whale Galaxy with the Vaonis Vespera II: 55 min from Bortle 6
- Whale Galaxy with the Vaonis Vespera Pro: 2 h 02 min from Bortle 6
- Whale Galaxy with the Vaonis Vespera 3: 52 min from Bortle 6
- Whale Galaxy with the Vaonis Vespera Pro 2: 1 h 56 min from Bortle 6
- Whale Galaxy with the Unistellar eQuinox 2: 49 min from Bortle 6
- Whale Galaxy with the Unistellar Odyssey: 3 h 46 min from Bortle 6
- Whale Galaxy with the Celestron Origin: 14 min from Bortle 6
- Whale Galaxy with the Celestron Origin Mark II: 20 min from Bortle 6
All telescopes for the Whale Galaxy · All targets for the DWARF II