How long to image the NGC 6781 with the Celestron Origin
From a Bortle 6 suburban sky, the Celestron Origin needs about 1 h 07 min (405 subs of 10 s) for a solid image of the NGC 6781. A quick look takes 17 min; a showpiece 4 h 30 min. Under a Bortle 3 rural sky the solid figure drops to 23 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 4% 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 | 5 min28 subs | 18 min110 subs | 1 h 13 min439 subs |
| Bortle 2Typical dark site | 5 min30 subs | 20 min119 subs | 1 h 19 min475 subs |
| Bortle 3Rural | 6 min34 subs | 23 min136 subs | 1 h 31 min544 subs |
| Bortle 4Rural / suburban transition | 7 min45 subs | 30 min178 subs | 1 h 58 min710 subs |
| Bortle 5Suburban | 10 min61 subs | 41 min244 subs | 2 h 42 min974 subs |
| Bortle 6Bright suburban | 17 min102 subs | 1 h 07 min405 subs | 4 h 30 min1,620 subs |
| Bortle 7Suburban / urban transition | 30 min179 subs | 1 h 59 min713 subs | 7 h 55 min2,852 subs |
| Bortle 8City | 50 min298 subs | 3 h 18 min1,191 subs | 13 h4,764 subs |
| Bortle 9Inner city | 1 h 32 min553 subs | 6 h 08 min2,211 subs | 25 h8,842 subs |
Power and kit for this session
Allowing for slewing, focusing and rejected subs, that is about 1 h 28 min of run time. The Origin’s battery (rated about 6 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.)
- portable power station 300W AC outletRuns the supplied 12 V adapter in the field; the dew shield and heater are already built in.
- 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 Origin →
How it frames
The NGC 6781 is 1.8′ across. The Origin frames 1.27° × 0.85° at 1.48″ per pixel, so it fills 4% of the frame’s short side.
Longer subs
10 s auto subs (15 s with the Nebula Filter); manual 1 to 30 s on the alt-az mount, longer only with the EQ wedge, and 60 s and up needs the StarSense Autoguider too. Time for a solid image by sub length:
| Sub length | Bortle 3 | Bortle 5 | Bortle 7 |
|---|---|---|---|
| 10 s | 23 min136 subs | 41 min244 subs | 1 h 59 min713 subs |
| 15 s | 21 min85 subs | 39 min156 subs | 1 h 57 min469 subs |
| 30 s | 20 min40 subs | 37 min75 subs | 1 h 56 min232 subs |
With and without the dual-band filter
| Filter | Bortle 3 | Bortle 5 | Bortle 7 |
|---|---|---|---|
| No filter | 23 min136 subs | 41 min244 subs | 1 h 59 min713 subs |
| dual-band (Nebula Filter), drawer | 22 min134 subs | 28 min167 subs | 52 min310 subs |
The Origin has no built-in dual-band filter. Filter drawer takes 1.25-inch or 2-inch filters, including dual-band; Celestron sells an optional Nebula Filter. On an emission target like this it is the single biggest upgrade you can make.
About the NGC 6781
A ghostly ring planetary in Aquila, larger and fainter than the Ring Nebula. Dual-band recommended.
Aquila planetary · Planetary nebula in Aquila · magnitude 11.4 · 1.8′ · best in Jun, Jul, Aug. Reachable from mid-northern latitudes (UK, northern US, central Europe) and from the south.
Planetary nebulae are small but intensely bright per pixel in OIII and H-alpha, so they respond very well to a dual-band filter and do not need much time for the main shell. The faint outer halos most of them have are a different proposition and need hours. Keep subs short if the central region saturates.
About the Celestron Origin
The first-generation Origin: a 6-inch f/2.2 RASA in a smart package and the fastest system here by a wide margin. Superseded by the Mark II in late 2025 and no longer sold new; Celestron offers a camera upgrade to the Mark II sensor.
10 s auto subs (15 s with the Nebula Filter); manual 1 to 30 s on the alt-az mount, longer only with the EQ wedge, and 60 s and up needs the StarSense Autoguider too. Filter drawer takes 1.25-inch or 2-inch filters, including dual-band; Celestron sells an optional Nebula Filter.
Longer subs matter most under dark skies, where read noise rather than skyglow sets the floor. From a city the difference between 10 s and 30 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 NGC 6781 from a Origin? Email it with your total time and sky to [email protected] and it goes here, credited.
Same target, other telescopes
- NGC 6781 with the ZWO Seestar S50: 2 h 42 min from Bortle 6
- NGC 6781 with the ZWO Seestar S50 Pro: 3 h 02 min from Bortle 6
- NGC 6781 with the ZWO Seestar S30: 3 h 09 min from Bortle 6
- NGC 6781 with the ZWO Seestar S30 Pro: 3 h 16 min from Bortle 6
- NGC 6781 with the DwarfLab DWARF 3: 3 h 22 min from Bortle 6
- NGC 6781 with the DwarfLab DWARF mini: 2 h 40 min from Bortle 6
- NGC 6781 with the DwarfLab Draco: 2 h 08 min from Bortle 6
- NGC 6781 with the DwarfLab DWARF II: 15 h from Bortle 6
- NGC 6781 with the Vaonis Vespera II: 4 h 15 min from Bortle 6
- NGC 6781 with the Vaonis Vespera Pro: 9 h 32 min from Bortle 6
- NGC 6781 with the Vaonis Vespera 3: 4 h 04 min from Bortle 6
- NGC 6781 with the Vaonis Vespera Pro 2: 9 h 05 min from Bortle 6
- NGC 6781 with the Unistellar eQuinox 2: 3 h 52 min from Bortle 6
- NGC 6781 with the Unistellar Odyssey: 18 h from Bortle 6
- NGC 6781 with the Celestron Origin Mark II: 1 h 33 min from Bortle 6
All telescopes for the NGC 6781 · All targets for the Origin