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Book a short-exposure core set for Cen A, and make it a campaign habit

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Processing the 21 Jul Centaurus A data showed the nucleus is saturated: a
single 300 s luminance sub reads 65313 ADU in the core, so the deep stack
is clipped there and the core cannot be recovered by processing. The only
fix is more data at shorter exposures.

plans/hdrcore-t32.txt is that data: L 8x60s, 8x15s and 8x5s plus RGB
5x30s, all BIN2 so the frames register against the deep stack without
rescaling. The ladder spans a factor of 60 below the 300 s subs, which
covers the unknown true peak of the nucleus, and the RGB gives the core
its colour. 18.2 minutes of imaging, about 25 points.

Uploaded to T32 and verified byte-identical, then booked for the evening
of 22 Jul, 18:50-19:50 SSO local, which is the same window in which the
deep run actually succeeded (T32 has a 35 degree elevation floor and Cen A
is an evening target). Verified in MySummary; quota now 7:05 of 8:00.

The wider point is recorded in CAMPAIGN.md: bright targets need a short
set budgeted alongside the deep run. NGC 6744 has already been shot
without one, and 47 Tuc and the SMC in queue #5 will certainly need one,
a globular cluster core being the fastest thing there is to saturate.
This commit is contained in:
Laurence 2026-07-21 13:41:23 +01:00
parent 6ba6024192
commit 7bf834a184
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19
CAMPAIGN.md
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@ -80,6 +80,7 @@ actual bill, and treat any not-yet-observed scope's card rate as +/-60%.
| 749230 | T8 | 26 Jul | 21:35-23:55 | catspaw-t8.txt | ~146 (25% moon disc.) | still booked |
| 749302 | T32 | 21 Jul | 18:50-21:50 | cena-t32.txt | ~350 (x1.6 rate, 25% moon disc.) | COMPLETED, billed 160. EVENING slot: T32 has a 35 deg elevation floor and Cen A culminates ~17:10 before dark, sinking to 11 deg by the old 00:35 slot (which could never have run). Ran 18:50-21:16, finishing 34 min early (plan complete, not a fault); images landed under /images/qisback/T32/NGC5128 |
| (id not captured) | T8 | 22 Jul | 21:45-00:45 | cra-t8.txt | ~250 | booked + MySummary-verified 2026-07-21 11:45 UTC. This is queue #2 finally placed: see the resolution note below. Runs 11:45-14:45 UTC 22 Jul |
| (id not captured) | T32 | 22 Jul | 18:50-19:50 | hdrcore-t32.txt | ~25 | booked + MySummary-verified 2026-07-21 13:30 UTC. HDR core set for the 21 Jul Cen A data, whose nucleus is saturated: see the note below. Runs 08:50-09:50 UTC 22 Jul, immediately before the T8 run that night |
| 749314 | T33 | 21 Jul | 00:05-00:50 | ngc104-test.txt | 0 (free) | booked + grid-verified 2026-07-21 08:55 UTC. 47 Tuc first-light retry, third attempt. Runs 14:05-14:50 UTC 21 Jul. Reschedule flag again No (free scopes never rebook) |
The T33 first-light test is now on its THIRD booking (749314); the two prior free
@ -102,6 +103,24 @@ Verify every booking via Edit.aspx?id= probing (sequential ids), NOT the grid.
| 5 | GRAS008 | 2026-08-08T02:35:00 | 2026-08-08T06:05:00 | 2:35 AM | 6:05 AM | smc47tuc-t8.txt | ~390 |
| 6 | GRAS032 | 2026-08-09T03:05:00 | 2026-08-09T06:05:00 | 3:05 AM | 6:05 AM | tarantula-t32.txt | ~365 |
| 7 | (T70, blocked: server unreachable) | night TBD before 5 Aug | ~2.5h | | | scorpius-t70.txt (in scratch, re-upload needed) | ~238 |
| 8 | BOOKED 2026-07-21 for 22 Jul 18:50-19:50 (see table above) | | | | | hdrcore-t32.txt | ~25 |
### Short-exposure core sets are now part of the campaign
The 21 Jul Cen A data came back with a saturated nucleus: a single 300 s
luminance sub reads 65313 ADU in the core, so the deep stack is clipped there
and no amount of processing recovers it. plans/hdrcore-t32.txt is the fix, an
exposure ladder (L 8x60s, 8x15s, 8x5s, RGB 5x30s, all BIN2 to match) that
blends in under the clipped core. It costs about 25 points, roughly a sixth of
what the deep run cost, and the same trick applies to any bright target.
**Apply this to the rest of the queue.** NGC 6744 (already shot, 19 Jul) has a
bright nucleus and probably needs the same treatment; 47 Tuc and the SMC
(queue #5) certainly will, since a globular cluster core saturates fast. Before
each remaining bright-target run, budget an extra ~25 points and an hour of
reservation quota for a matching short set, and cut the ladder from the deep
plan's exposure rather than guessing: shortest sub = deep sub / 60 is what was
used here.
### Session 2026-07-21 ~08:55 UTC (booking round run early, before Cen A ran)