From York Tam post on Facebook:
1. get peak tower info:
淩霄閣 peak tower co-ordinate from google maps:
22.2712357,114.1499638
height: 428 m (389m ?)
https://en.wikipedia.org/wiki/Peak_Tower
2. get approximate photo location distance:
distance from google map:
8300 km approx
azimuth is calculated to be ~ 2.94 deg above horizon (top of 2 tower)
3. use mooncalc
date and time:
6 Sep 2022 00:56 HKT
4 use this vincenty calculation for more accurate positioning: which gives this location:
22.3104181° N 114.2186257° E
(assuming mooncalc's moon azimuth is correct, convert to its back angle, ie 58.47 degrees)
so these different approaches have a discrepancy of 100 to 200 metres.(ellipsoid model WGS84 ok?)
suggestions:
-calibration day: do some site survey to verify the co-ordinates, and if location is suitable, a few days or week before. better to have some landmarks for aligning the camera, eg corner of nearby building
always have a plan b
bring an equatorial mount will be very helpful for tracking. , even star tracker, or alt-az is helping
- know/ guestimate the sources of error and tolerances
next occurrence will be 27 to 28 days later
5 Oct 2022 01:00 HKT, waxing gibbous
31 Oct 2022, 22:52 HKT here, first quarter
26 Nov 2022, 19:33 HKT, here , waxing crescent
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