Sky transparency — night of 7–8 October 2026

No cloud onset detected. The transparency index held at 100 (IQR 95–101) across 53 light frames. Guiding held at 0.97″ RMS (RA 0.65″, Dec 0.73″) over 5.0 h; the worst minute was 4.14″ at 03:44. Morning sky flats: 63 frames (O 21, S 21, H 21), 06:41–06:45, auto-exposure 1.2–1.6 s.

Transparency index

100 · IQR 95–101

Light frames

Autofocus runs

Failures

2 · solve + PHD2

Guide RMS

0.97″ · RA 0.65 · Dec 0.73

Normalised transparency index, by filter

100 = that target and filter's own clear‑sky median (this night's own pre-cloud median). Shaded columns are autofocus runs; the first target is named at the top left and dashed vertical rules mark each target change; ticks along the base are errors.

H α O III S II ▲ Plate solve failed ◆ PHD2 error

All‑sky background brightness

Mean luminance of the upper sky per all‑sky still — independent of anything N.I.N.A. recorded. The camera auto‑exposes, so this is an instrumental number, not photometry.

PHD2 guiding

RMS tracking error per minute from the PHD2 guide log, taken about zero rather than about each minute's mean, so slow drift counts as error. 3073 guide frames over 5.0 h of guiding in 9 sessions; the gaps are slews, dither settles and autofocus runs, when PHD2 was not guiding. PHD2 discarded 3 further frames — usually a lost star. The worst minute (4.14″ at 03:44) is clamped at the top of the plot.

RA RMS Dec RMS ◆ PHD2 error

All‑sky frames at the key moments

Times come from the still filenames, so they line up with the charts exactly.

All-sky at 20:30 — **20:30** · start of night

All-sky at 05:51 — **05:51** · peak brightness 47.8

All-sky at 06:19 — **06:19** · end of night

Clear‑sky reference medians

The divisors behind the index — median detected stars per light sub.

Target	Filter	Median stars	Frames	Source
IC 434 Panel 1	H	178	4	tonight, clear frames
IC 434 Panel 1	O	132	4	tonight, clear frames
IC 434 Panel 1	S	269	4	tonight, clear frames
IC 434 Panel 2	H	220	4	tonight, clear frames
IC 434 Panel 2	O	196	4	tonight, clear frames
IC 434 Panel 2	S	371	4	tonight, clear frames
IC 434 Panel 3	H	305	4	tonight, clear frames
IC 434 Panel 3	O	215	3	tonight, clear frames
M 17	H	711	8	tonight, clear frames
M 17	O	1208	8	tonight, clear frames
M 17	S	1804	6	tonight, clear frames

Event timeline

All observatory events with their attributed causes.

03:16:58solve failedASTAP plate solve failedunexplained

03:17:36solve failedASTAP plate solve failedunexplained

All 144 frames (excludes the 63 sky flats — no stars to detect)

Time	Class	Target	Filter	Exp	Stars	HFR	Index
20:30:38	autofocus	M 17	L	5s	285	3.91	—
20:30:56	autofocus	M 17	L	5s	743	2.16	—
20:31:11	autofocus	M 17	L	5s	911	1.81	—
20:31:25	autofocus	M 17	L	5s	815	1.99	—
20:31:40	autofocus	M 17	L	5s	673	2.51	—
20:32:01	autofocus	M 17	L	5s	351	3.58	—
20:32:21	autofocus	M 17	L	5s	219	4.57	—
20:32:41	autofocus	M 17	L	5s	419	3.33	—
20:32:56	autofocus	M 17	L	5s	240	4.77	—
20:33:11	autofocus	M 17	L	5s	192	6.10	—
20:33:31	autofocus	M 17	L	5s	949	1.78	—
20:40:08	light	M 17	H	300s	374	3.67	53%
20:45:41	light	M 17	H	300s	357	3.79	50%
20:51:34	light	M 17	H	300s	312	4.00	44%
20:52:26	autofocus	M 17	L	5s	568	2.56	—
20:52:46	autofocus	M 17	L	5s	174	7.37	—
20:53:05	autofocus	M 17	L	5s	232	5.34	—
20:53:21	autofocus	M 17	L	5s	286	4.42	—
20:53:36	autofocus	M 17	L	5s	442	2.97	—
20:53:55	autofocus	M 17	L	5s	728	2.24	—
20:54:16	autofocus	M 17	L	5s	994	1.82	—
20:54:35	autofocus	M 17	L	5s	936	1.92	—
20:54:56	autofocus	M 17	L	5s	711	2.51	—
20:55:15	autofocus	M 17	L	5s	475	3.39	—
20:55:30	autofocus	M 17	L	5s	271	4.49	—
20:55:51	autofocus	M 17	L	5s	1022	1.77	—
21:01:49	light	M 17	H	300s	588	2.88	83%
21:07:49	light	M 17	O	300s	1141	2.92	94%
21:13:38	light	M 17	O	300s	1176	2.83	97%
21:19:22	light	M 17	O	300s	1180	2.80	98%
21:24:56	light	M 17	O	300s	1049	3.00	87%
21:30:54	light	M 17	S	300s	1655	2.87	92%
21:36:34	light	M 17	S	300s	1572	2.95	87%
21:42:29	light	M 17	S	300s	1903	2.63	105%
21:47:59	light	M 17	S	300s	2266	2.28	126%
21:48:31	autofocus	M 17	L	5s	1070	1.50	—
21:48:45	autofocus	M 17	L	5s	177	6.06	—
21:49:00	autofocus	M 17	L	5s	205	5.24	—
21:49:15	autofocus	M 17	L	5s	338	3.89	—
21:49:30	autofocus	M 17	L	5s	459	2.85	—
21:49:50	autofocus	M 17	L	5s	917	1.75	—
21:50:10	autofocus	M 17	L	5s	958	1.57	—
21:50:30	autofocus	M 17	L	5s	753	2.14	—
21:50:50	autofocus	M 17	L	5s	495	2.79	—
21:51:05	autofocus	M 17	L	5s	274	3.93	—
21:51:20	autofocus	M 17	L	5s	219	5.06	—
21:51:40	autofocus	M 17	L	5s	921	1.69	—
21:57:37	light	M 17	H	300s	850	2.35	120%
22:03:15	light	M 17	H	300s	752	2.52	106%
22:08:46	light	M 17	H	300s	711	2.61	100%
22:09:36	autofocus	M 17	L	5s	874	1.72	—
22:09:51	autofocus	M 17	L	5s	189	5.78	—
22:10:06	autofocus	M 17	L	5s	250	4.40	—
22:10:21	autofocus	M 17	L	5s	429	2.89	—
22:10:36	autofocus	M 17	L	5s	624	2.26	—
22:10:56	autofocus	M 17	L	5s	869	1.73	—
22:11:16	autofocus	M 17	L	5s	723	2.05	—
22:11:36	autofocus	M 17	L	5s	461	2.85	—
22:11:51	autofocus	M 17	L	5s	315	3.54	—
22:12:06	autofocus	M 17	L	5s	176	4.93	—
22:12:26	autofocus	M 17	L	5s	859	1.74	—
22:18:25	light	M 17	H	300s	823	2.38	116%
22:24:13	light	M 17	O	300s	1232	2.60	102%
22:29:48	light	M 17	O	300s	1208	2.62	100%
22:35:20	light	M 17	O	300s	1263	2.52	105%
22:40:53	light	M 17	O	300s	1263	2.49	105%
22:47:20	light	M 17	S	300s	1726	2.57	96%
22:53:17	light	M 17	S	300s	1804	2.46	100%
02:27:31	autofocus	IC 434 Panel 1	L	5s	187	1.49	—
02:27:46	autofocus	IC 434 Panel 1	L	5s	64	5.08	—
02:28:01	autofocus	IC 434 Panel 1	L	5s	83	3.66	—
02:28:16	autofocus	IC 434 Panel 1	L	5s	106	2.53	—
02:28:31	autofocus	IC 434 Panel 1	L	5s	194	1.60	—
02:28:51	autofocus	IC 434 Panel 1	L	5s	179	1.52	—
02:29:11	autofocus	IC 434 Panel 1	L	5s	166	1.89	—
02:29:31	autofocus	IC 434 Panel 1	L	5s	107	2.84	—
02:29:50	autofocus	IC 434 Panel 1	L	5s	79	4.07	—
02:30:11	autofocus	IC 434 Panel 1	L	5s	58	5.31	—
02:30:31	autofocus	IC 434 Panel 1	L	5s	190	1.52	—
02:37:53	light	IC 434 Panel 1	H	300s	180	2.63	101%
02:43:21	light	IC 434 Panel 1	H	300s	178	2.67	100%
02:48:52	light	IC 434 Panel 1	H	300s	165	2.79	93%
02:54:33	light	IC 434 Panel 1	H	300s	164	2.79	92%
03:00:19	light	IC 434 Panel 1	O	300s	132	2.89	100%
03:05:48	light	IC 434 Panel 1	O	300s	140	2.68	106%
03:11:21	light	IC 434 Panel 1	O	300s	126	2.82	95%
03:16:54	light	IC 434 Panel 1	O	300s	130	2.64	98%
03:22:50	light	IC 434 Panel 1	S	300s	267	2.48	99%
03:28:26	light	IC 434 Panel 1	S	300s	269	2.54	100%
03:33:58	light	IC 434 Panel 1	S	300s	263	2.61	98%
03:39:29	light	IC 434 Panel 1	S	300s	271	2.43	101%
03:40:11	autofocus	IC 434 Panel 2	L	5s	217	1.45	—
03:40:26	autofocus	IC 434 Panel 2	L	5s	56	5.67	—
03:40:41	autofocus	IC 434 Panel 2	L	5s	81	4.43	—
03:40:56	autofocus	IC 434 Panel 2	L	5s	105	3.19	—
03:41:10	autofocus	IC 434 Panel 2	L	5s	160	2.05	—
03:41:31	autofocus	IC 434 Panel 2	L	5s	195	1.36	—
03:41:51	autofocus	IC 434 Panel 2	L	5s	208	1.47	—
03:42:11	autofocus	IC 434 Panel 2	L	5s	171	2.15	—
03:42:26	autofocus	IC 434 Panel 2	L	5s	98	3.26	—
03:42:41	autofocus	IC 434 Panel 2	L	5s	68	4.53	—
03:43:01	autofocus	IC 434 Panel 2	L	5s	201	1.43	—
03:50:23	light	IC 434 Panel 2	H	300s	233	2.25	106%
03:55:55	light	IC 434 Panel 2	H	300s	220	2.36	100%
04:01:23	light	IC 434 Panel 2	H	300s	208	2.46	95%
04:02:16	autofocus	IC 434 Panel 2	L	5s	186	1.62	—
04:02:31	autofocus	IC 434 Panel 2	L	5s	55	5.13	—
04:02:46	autofocus	IC 434 Panel 2	L	5s	73	3.86	—
04:03:01	autofocus	IC 434 Panel 2	L	5s	98	2.86	—
04:03:16	autofocus	IC 434 Panel 2	L	5s	164	1.88	—
04:03:36	autofocus	IC 434 Panel 2	L	5s	167	1.64	—
04:03:51	autofocus	IC 434 Panel 2	L	5s	163	1.85	—
04:04:11	autofocus	IC 434 Panel 2	L	5s	119	2.56	—
04:04:26	autofocus	IC 434 Panel 2	L	5s	69	3.80	—
04:04:41	autofocus	IC 434 Panel 2	L	5s	51	4.86	—
04:04:56	autofocus	IC 434 Panel 2	L	5s	180	1.57	—
04:10:53	light	IC 434 Panel 2	H	300s	208	2.48	95%
04:16:35	light	IC 434 Panel 2	O	300s	196	2.49	100%
04:22:05	light	IC 434 Panel 2	O	300s	187	2.45	95%
04:27:35	light	IC 434 Panel 2	O	300s	199	2.25	102%
04:33:08	light	IC 434 Panel 2	O	300s	191	2.22	97%
04:38:45	light	IC 434 Panel 2	S	300s	371	2.07	100%
04:44:18	light	IC 434 Panel 2	S	300s	371	2.06	100%
04:49:48	light	IC 434 Panel 2	S	300s	364	2.06	98%
04:55:20	light	IC 434 Panel 2	S	300s	366	1.95	99%
04:56:01	autofocus	IC 434 Panel 3	L	5s	137	1.37	—
04:56:16	autofocus	IC 434 Panel 3	L	5s	61	4.90	—
04:56:31	autofocus	IC 434 Panel 3	L	5s	88	3.52	—
04:56:46	autofocus	IC 434 Panel 3	L	5s	116	2.42	—
04:57:01	autofocus	IC 434 Panel 3	L	5s	193	1.41	—
04:57:21	autofocus	IC 434 Panel 3	L	5s	151	1.41	—
04:57:36	autofocus	IC 434 Panel 3	L	5s	175	1.66	—
04:57:56	autofocus	IC 434 Panel 3	L	5s	104	2.68	—
04:58:16	autofocus	IC 434 Panel 3	L	5s	63	3.89	—
04:58:36	autofocus	IC 434 Panel 3	L	5s	50	4.88	—
04:58:51	autofocus	IC 434 Panel 3	L	5s	50	6.03	—
04:59:11	autofocus	IC 434 Panel 3	L	5s	151	1.40	—
05:06:35	light	IC 434 Panel 3	H	300s	277	1.90	91%
05:12:08	light	IC 434 Panel 3	H	300s	302	1.82	99%
05:17:41	light	IC 434 Panel 3	H	300s	305	1.87	100%
05:23:17	light	IC 434 Panel 3	H	300s	313	1.87	103%
05:28:59	light	IC 434 Panel 3	O	300s	215	1.93	100%
05:34:30	light	IC 434 Panel 3	O	300s	216	1.91	100%
05:40:01	light	IC 434 Panel 3	O	300s	203	2.01	94%

Star counts come from Hocus Focus detection on each saved sub, tagged with the filter in place at exposure start and the target then being imaged. Frames inside completed autofocus runs are excluded. Still capture times come from the AllSky filenames. All times are local.