Tuesday: Back to the observatory to dig deeper on location and time. I used three aerial photography and mapping services to locate my pier inside the observatory to 1/10 of a second of arc. Then added the fractions of a second to my existing site coordinates just for the sake of it.
AWR's LST [Local Sidereal Time] remains a hurdle. AWR shows LST constantly on the IH2 [paddle] screen. The problem is that an online LST calculator and C-Du-C do not agree with AWR by two whole minutes! I've been here before when AWR didn't change for summer time. AWR's RTC [Real Time Clock] had to be changed to bring it into line with reality. Dare I do this with the two minutes?
Local Sidereal Time Clock An online calculator for Local Sidereal Time.
In theory, if you place the cursor on the Meridian in C-Du-C it should show LST for the site. Two minutes behind compared to AWR? As was the LST calculator. I cannot believe that a calculator would remain online unless it was useful. i.e ACCURATE!
I had to increase my real Longitude by 0.63° to make the calculator show the same LST as AWR. So there is something very wrong there. If AWR is using the wrong time then it can't locate anything in the sky. Guess what? It can't even find the Sun and the Moon!
Earlier rain has cleared to bits of blue sky. Lunch over, so it is back to the fray! Wish me luck! I may be some time.
I adjusted the AWR's indicated LST via RTC [Real Time Clock] until I got a match within 5 seconds of the LST calculator and C-Du-C. Then I carefully confirmed the East-> horizontal Parking Position. Before a Goto slew [and Meridian Flip] to the Sun hiding behind thin cloud. Guess what? It missed!
There was no sign of the sun in the Lacerta prism's heat shield port. Usually the bright disk passes across the heat shield and can be brought back with the control paddle. I repeated the exercise and returned back to Home at intervals during the afternoon without greater success. The promised clearing to sunshine never happened. So I'm back to square one and none the wiser.
I have performed this Flip/Goto slew dozens of times after lunch. Having turned off the drives to avoid a voluntary Meridian Flip in my absence. [Though this has never happened.] The telescope is left pointing slightly east and must be returned Home and registered [calibrated or synced] there before I can start slewing again from scratch. The AWR system doesn't remember where it is following a switch OFF.
Close clearances and cable dressing do not allow a Meridian Flip without my careful supervision. The big Herschel prism will happily sweep the laptop off the desk if the focuser is left extended. Then there's the big computer monitor jutting from both sides of the huge pier. USB3 camera cables must be detached and rerouted afterwards to avoid unexpected tension during the slew.
It's very odd how the changing seasons exercise different areas of the telescopes' quite considerable envelope. High summer sun or low winter sun may go unnoticed on smaller or shorter instruments. When you are swinging big tubes more than two meters long, with extra "dangly" bits, in a rather limited space, it makes a huge difference.
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