8.3.19 Solar with binoviewer.

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Friday 8th 50/45F, Severe gales from NW but sunny morning. Fears of too much noise in the dome were soon dismissed.

WL in the 7" with Lacerta 2" prism and SC. A tiny spot near the center of the disk. Only about the size of Mercury in transit. Oddly shaped, but without obvious detail or penumbra even up to 180x using the 12.4mm.

H-a: I tried the binoviewers without a GPC using a 1.25" star diagonal but was unable to come to [inward] focus. Straight through was okay without any extensions. So I do still have a serious inward focus problem with the star diagonal. I need 100mm more inward focus but can't get it without GPC amplification.

Confirmed the 15mm still showed full disk in the bare binoviewers. While 12.4mm was too much to show any sky around the sun's disk. This is not some whim on my part. With so little in the way of sunspots, on the disk, I want the limb to check for prominences.

12.00  57/45F I tried the 2.6x GPC on the bnvr. nosepiece but even with the 32mm EPs it gives far too much power.

Tried the TS 1.6x GPC in the binoviewer nose with 32mms. This works well but provides only a small solar disk. 26mm "straight through" with 1.6x GPC in the binoviewer nose nicely fills the field of view. Leaving a small annulus [for spotting prominences] and good image size. Note how I'm having to pull both 2" spigots out of their sockets to gain extra length over the 40mm extension. [Image left.]  I need another 60mm extension.

12.30 51/45F The 1.6x smooths out the etalon sweet spot to provide all disk texture instead of a sharp ring. Beginning to find the tolerance level of my neck from tipping my head back while doing the splits!!  So I fetched my adjustable height chair. Much better than standing but not perfect. It needs back support to allow me to relax my body while I am leaning back. Now the sun's entire surface really snaps into view. With the small black spot surrounded in a large "childhood inoculation scar" of lighter [plage] material.

Easily the best views I have ever had in H-alpha! It is a huge relief that I can see a large, but full solar disk while still using comfortable eyepieces. Not so happy about the continuing problem of no star diagonal. I'm going to have to buy another 2x Barlow. One with a removable optical nosepiece to fit directly onto the binoviewer. TS sells several such Barlows but claim they will magnify by 2.6x in a binoviewer. Which is exactly the claimed power of the their own GPC. Am I wasting time and money on what already amounts to the same thing? Perhaps I need to start looking for 40mm EPs to go with the existing 2.6x GPC? 

13.00 53/46F It is fascinating how the racing cloud affects the H-a image. The plage is selectively enhanced with certain cloud densities. It is frustrating when the images vanishes altogether but in between the disturbance around the spot is standing out starkly. The sun's surface has many scattered, black pores. Which I am seeing properly for the very first time thanks to the spreading of the sweet spot. At last three areas of plage are clearly visible now.

There have been some fierce gusts today but thankfully the slit was always facing away from the wind. Shame it is getting so cloudy now. Nearly lunch time, so there's a chance it might improve later. Though it may be impossible to observe even if the wind drops a bit as forecast. It is also swinging to the west where the slit will be pointing this afternoon! The wind dropped a little but the seeing followed on downwards.

To finish off the day I fitted the upstanding, plastic underskirt. It was much stiffer and tougher than I had imagined. Leading to a rather wavy top edge by the time I had screwed it to the [rounded] octagon top ring at 4" intervals. Now I'm wondering how it will behave in very warm weather. Will it even out with softening or expand into a corrugated mess? I haven't had a chance to try a full dome rotation out of respect for the wind. More on this tomorrow before the gales start again.

Click on any image for an enlargement.

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