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Tomorrow, 31st December 2019, is finally promised to be sunny all day. Starting windy from the NW but dying down over the course of the day. That shouldn't bother me too much with the sun in the SE until lunch time. I am getting fed up with losing captures to wind movement. The 7" f/12 is quite close to the slit and today the wind was straight on. Barely a second passed without some bodily movement of the sun on the monitor.
Initial thoughts are to resurrect the folded 7" OTA. Which has been in storage since I rebuilt the long, straight version. It's not as if I am using a dewshield on the 7". That would just catch even more wind. No dewshield means some dew. Dew heater bands can solve that problem. The open framework of the folded 7" would avoid wind problems but means a hot, unfiltered beam being folded back and forth within the open framework. I don't think the folding [coated Zerodur] mirrors will be much bothered by the heat. Nobody else has access to the observatory so the risk of personal injury is limited to my own idiocy.
I can also remove the 90mm Vixen f/11. Which is hardly ever used but helps to balance the asymmetrically mounted, 6" H-alpha OTA. The smaller refractor is handy for a quick look at the sun in white light and has a permanent solar foil filter over the objective. The 90mm adds some weight, moment and only a very little wind drag.
With the new, 6" f/10 lens coming over the horizon I really have to decide how best to proceed. I am now concentrating almost exclusively on H-a, solar imaging. No point investing so much time and expense unless I maximise my results. I have wasted decades without any serious goal for my astronomical activities. In fact most of my time has been spent building equipment rather than actually looking at the sky. The local trees and tall hedges made observation extremely limited. Which is my excuse and I'm sticking to it.
I could just mount the 6" H-a OTA alone on the big mounting. Or even use the Fullerscopes MkIV mounting? Though that doesn't have proper drives since I cooked the poor old, original, Fullerscopes VFO, drive controller with 7 hours of Mercury Transit. That was with the 7" aboard the MkIV! The old mounting is still functional, thanks to its replacement, stainless steel shafts. Though it could do with a new paint job after years of living under a leaky tarpaulin. The MkIV can easily handle a 6" f/10 and has a massive, welded steel pier to support it. But where would it be sited? No point in returning to the ground where the view and thermal effects from the shrubbery are concentrated.
Despite the endless problems with the AWR stepper motor, Goto drives I have become completely spoilt by the drive accuracy. Both adjustable speed control paddles are very user-friendly. That is when the drives keep going and it doesn't stop tracking apparently randomly. The ease of moving the sun around in the camera's small field of view is quite mind blowing and would be very painful to give up now. I probably shan't live long enough to fit a fully working AWR system to the MkIV. Not to mention the expense. A new VFO controller might be doable though.
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