Calcium Sun - 6th April

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Calcium Sun - 6th April

Post by marktownley »

Tuesday offered a shift in wind direction for me, more north westerly, and experience tells me that despite MeteoBlue saying 3" seeing it would be locally better. This direction often brings cumulus clouds, and the blue gaps in between the clouds often offer some decent seeing. This was confirmed when I started off with the CaK full disk at 60mm f16, and a considerably more stable view than of recent days.

ImageCaK-FD-bw by Mark Townley, on Flickr

ImageCaK-FD-colour by Mark Townley, on Flickr

Today also offered a chance to continue my CaK triple stack journey, I tried a few configurations i'd thought of the previous evening. Whatever I try I get consistently better results in double stack, and using the sky bender I am able to tune the second filter of the stack to give maximum contrast which in turn reveals the chromospheric fringe and proms. Double stack also has about 3-4 time shorter exposure which when fishing in the better moments of seeing is a must...

Deciding to chance it I went for 100mm f28 with the IMX174, and taking 4000 frame captures figured there would be enough good sub frames to make a decent image: Firstly departing AR12813... All closeup images have a decent amount of zoom left in them, so double click for the view in Flickr.

Imagear12813-CaK-bw by Mark Townley, on Flickr

Imagear12813-CaK-colour by Mark Townley, on Flickr

And the decaying area of plage, yesterday had several pores, but was struggling to make them out today...

ImageMagnetic-active-region-CaK-bw by Mark Townley, on Flickr

ImageMagnetic-active-region-CaK-colour by Mark Townley, on Flickr

On the north east limb there was more plage but was struggling to get a decent view of this one.

ImageEast-patch-cak-bw by Mark Townley, on Flickr

ImageEast-patch-cak-colour by Mark Townley, on Flickr

Then, just to be silly, and because i'm testing out a couple of different optical configurations, I went for 100mm f46, again with the IMX174, I knew seeing wasn't up to it, so increased the frame count to 6000 with a view of stacking only the very best. Some silly colour just for fun too!

ImageNE-limb-cak-close-bw by Mark Townley, on Flickr

ImageNE-limb-cak-close-colour by Mark Townley, on Flickr

Imagear12813-cak-close-bw by Mark Townley, on Flickr

Imagear12813-cak-close-colour by Mark Townley, on Flickr

Then this cheeky little number came out of stacking, looks like there is some potential for this when in the constraints of the seeing...

Imagemagnetic-region-CaK-close-bw by Mark Townley, on Flickr

Imagemagnetic-region-CaK-close-colour by Mark Townley, on Flickr

Quite pleased with the last closeup, definitely my favourite from today and worth the full size view. I want to see if I can get somewhere around f40 for slightly better sampling. More CaK experiments for tomorrow assuming the blue skies carry on a bit more.

Hope you like.


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Re: Calcium Sun - 6th April


You certainly are working-hard to try out these experimental set-up's Mark. And in the cold too. Better you than me. Even the possibility of some snow in the SE, as has occurred in SW-Holland According to my Daughter there and with our temps today around 6 to 8-degsC, you are brave...

The close-up's of AR2813 are my favs - even though decaying as it nears the limb.

Terry (in the warm)...

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Re: Calcium Sun - 6th April

Post by dhkaiser »

Impressive results Mark.

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Re: Calcium Sun - 6th April

Post by Montana »

Oooh these make my mouth water, especially the last few shots :bow :hamster:


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Re: Calcium Sun - 6th April

Post by Carbon60 »

Really excellent, Mark. Your Tinkering is working wonders. Congrats on SPoD :)


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