30.3.19

30.03.19 Solar A tiny spot in WL & H-a.

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Saturday: A long, sunny day is promised. I just hope there is something to see. A big spot group or a prom would do nicely. Though either is highly unlikely. Particularly since Gong H-a is showing a blank disk with only a few scrawny prominences.

60/58F continuous sunshine but a gusty wind from the SW blowing through the slit. A productive morning with surface detail captured in both WL and H-a. The question is why the WL detail isn't visible to the naked eye when it is so clear to the Neximage5?

I even tried the binoviewer with 2.6x GPC and Baader Solar foil to see if the prism was robbing me of this detail. The foil showed a marginally softer limb with more false colour but still no surface detail. The power must have been well over 300x using 20mm EPs. Just to be certain I wasn't fooling myself on binoviewer magnification I used a single eyepiece and 2x Orion Shorty Barlow for 450x. There was still plenty of light from the 7" when I rotated the single polarising filter in the Lacerta prism housing. The limb remained quite firm but still no surface detail!

The 2.6x GPC gave me a margin of 12mm from the focuser being fully in. While the 2x WO Barlow nose can't quite focus by only 3mm or 1/8". I removed the 2" focuser adapter to regain enough inward travel to reach focus just to confirm it.

Sunday: Out early 8.00am [7.00 Winter Time] to see if more was detail was visible before the heat of the day raised thermals. Still unable to see any surface detail in white light. I pushed the power well up but could see nothing. Only slight thermal boiling on the sun's limb.

A nice view in H-alpha including very even surface texture and a pair of proms at my 8 o'clock. Another prom nearby and a tiny one at 3.00. Nothing on the disk even at probably well over 130x. 1200mm focal length + binoviewers with 20mm EPs x2 Barlow nosepiece plus glass path length amplification. Very stable image. Despite the wind being opposite the slit it still managed to blow the shutters closed before I bolted them wide open again.

11.30 49/44F Clear sky but slightly milky around the sun. Strong wind from NW.
Returned after a break. Still nothing in WL.
H-alpha: I have bright round spot on the edge of a dark oval at my 4.00.
I'm inverted & L>R. So Gong shows it at 9.30.
The two obvious proms are at 2.00 on Gong H-a. My 8.00.

12.05 Pushed the power up with 20mm EPs for about 130x.
The bright spot is hemmed in by a dark line like a filament.
Another filament crosses the oval.

15.00 The disturbed area is now visible in white light as a tiny spot with smaller companion.
Surrounded in a little plage. Still tiny at 220x. A third and even smaller, dark spot has now appeared.
In H-a the previous oval area has become much larger and brighter overall. The appearance changes depending on the etalon sweet spot.

I am going to fit my Vixen 90/11 to the instrumental heap somehow. I noticed the spot immediately through that at various powers up to 50x. Reaching the eyepiece is the main problem with so much "junk" in the way. [H-a stack and Herschel prism.] There is nowhere sensible to overhang it towards the tailpieces of the bigger instruments.


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