I am rebuilding my 7" f/12 R35 iStar refractor for some white light solar, lunar and planetary imaging. The 7" was dismantled and stored safely away while I concentrated on H-alpha.
There was usual struggle with the long and heavy OTA. I needed the block and tackle to lift the 7" onto the spacer bars beside the 6". Which I had already mounted by hand from a stepladder.
Then
I had to make a new, shorter, tubular spacer to get four x 5kg weights onto the
end of the 50mm Ø Declination shaft. Those who have been paying attention will remember that I changed to a shorter Dec shaft for the solitary 6".
After refitting both telescopes I had to slide the 7" down through the rings to achieve more clearance of the dewshield from the dome lights. Then back up again to allow clearance of the Lacerta solar prism from the base ring.
Its unique Brewster Angle forces the eyepiece outwards in specific arcs at certain times of the year. Including the late afternoon as the sun's altitude sinks towards the south west in autumn. Uniquely forcing a minimum dome diameter for clearance. Which problem would never exist with a 90° solar prism.
A quick, visual check with the 2" Lacerta prism and 32mm EP showed the sun
was sharp edged but thermally wavy. The disk was devoid of any visible features. Tomorrow, I shall have to
attend to fine balancing with the worms withdrawn. This is to avoid
driving the telescopes "uphill" due to a lack of balance. Which can easily stall the stepper motors during a slew. I shall take a better image of the telescopes mounted together when there is lower contrast. Bright sunshine on the dome doesn't help the dark interior.
I have a horrible feeling that I shall have to remove both telescopes and refit the longer Dec shaft. The telescopes are already marginally heavier than the four counterweights. Which are right on the very end. With no room for more. So there's absolutely no allowance for anything to be added on the telescope side. Like a finder. Or sliding weights for longitudinal OTA balance. My back and shoulders are still aching from yesterday's foolishness.
You try carrying a complete and fragile 7" f/12 OTA up an 80° stepladder! Then up through a small trapdoor and out through the dog-kennel cut-out in the pier! The stupid thing is I had to remove the objective cell anyway once I had the telescope up there. I'd forgotten to fit the stubby dewshield. Which is trapped between the cell and countercell. Without the dewshield there is no way to protect the lens in winter. I add foam insulating tubes and plugs to reduce dewing when I open up for solar observation in the morning.
The longer shaft takes up more room and places the weights in more positions suitable for "head bangers" like me. I painted the weights white but it doesn't help when I am moving about within the dome. I'm always wearing a baseball type of cap to shield my eyes from the sun. Which blocks my view from anything above me. My mind is always on something other than impending brain surgery by blunt force impact! Perhaps I should have a haed hat with a peak? The sheer weight of the shaft is a hell of a lift when the big mounting is so far off the floor! Then there's the sheer weight of the Dec housing. The Tollok bushes have to be separated and then re-clamped. Woah! Thrice woah! 🙄
With my interest only in the Sun and Solar System objects a fork mount would have been perfectly adequate! Time for a redesign? I have some tasty, rectangular box sections in scrap aluminium just waiting for a new purpose.😉 No. That would mean they hang down over my present computer desk.
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