Sun disc of December 21st

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krakatoa1883
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Sun disc of December 21st

Post by krakatoa1883 » Thu Dec 21, 2017 4:33 pm

A very unfortunate month for solar observing and imaging, bad weather and office work kept me away from my telescopes, the Sun low in the sky is turbulent most of the time lowering image contrast and shaarpness. Moreover after careful testing I discovered to be one of the few unlucky men that got a pressure tuned LS50 with some problems of uniformity in the field of view. The scope is usable but could have been better.

Below are my images of today in poor seeing conditions and slightly hazy sky. Thanks for looking.
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sun20171221_filament.jpg
sun20171221_filament.jpg (77.72 KiB) Viewed 548 times
sun20171221_FD_H.jpg
sun20171221_FD_H.jpg (67.61 KiB) Viewed 548 times
sun20171221_FD_CaH.jpg
sun20171221_FD_CaH.jpg (68.04 KiB) Viewed 548 times
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Re: Sun disc of December 21st

Post by ffellah » Thu Dec 21, 2017 8:01 pm

Raf: these are good images despite the circumstances and conditions...

Happy Holidays !

Franco

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Re: Sun disc of December 21st

Post by Derek Klepp » Thu Dec 21, 2017 10:14 pm

Raf that Daystar Ca came up well.

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Re: Sun disc of December 21st

Post by Montana » Fri Dec 22, 2017 10:28 am

Looks like a nice active region, I haven't seen the Sun for days so it is nice to know what it looks like :bow :hamster:
If you are unhappy with the scope have you spoken to Lunt? is there anyway to fix it?
Alexandra

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Re: Sun disc of December 21st

Post by krakatoa1883 » Fri Dec 22, 2017 1:51 pm

Thanks to all for appreciation.

@Alexandra: some months ago I have been offered a LS60 with tilt tuning and a LS50 with FT focuser, and eventually I purchased the latter as I expected the pressure tuning be able to deliver more uniform images. In my sample, however, the sweet spot is slightly shifted toward one side of the field so that the area of best contrast is not at the very centre. Visually this is not important and even difficult to note, but with the CCD the full disc always shows one side of the Sun to be brighter and contrasted than the other. Turning the handle in or out makes the disc more uniform but the best position for uniformity doesn't correspond to the best tuning for CWL. Based on what I have read on the Internet this behavior is still within the quality bar of the product and it is not covered by warranty.
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Re: Sun disc of December 21st

Post by Ibbo » Fri Dec 22, 2017 10:27 pm

VNice images under the conditions

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Re: Sun disc of December 21st

Post by eroel » Sat Dec 23, 2017 1:19 am

Raf;
Well done.
Wish you the best for Christmas and New Year, from N.Y.,
Eric.

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Re: Sun disc of December 21st

Post by yltansg » Sat Dec 23, 2017 2:43 am

Hi Raf,

Nice collection. There is also some uneveness in my Lunt 50. Got used to it by now.

Alfred

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Re: Sun disc of December 21st

Post by krakatoa1883 » Sat Dec 23, 2017 12:41 pm

Thanks for comments. Today AR12692 seems larger than yesterday, with 17-18 small spots (at least two of them with a small penumbra), enjoy the view if you can.

Merry Christmas to all of you!
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Re: Sun disc of December 21st

Post by Carbon60 » Sun Dec 24, 2017 11:43 am

Good images, Raf. It's so difficult this time if year in the north. Nicely done.

All the best for the season.

Stu.
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Re: Sun disc of December 21st

Post by marktownley » Wed Dec 27, 2017 6:54 am

Nice shots! Can you try a different blocker with the 50?
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Re: Sun disc of December 21st

Post by krakatoa1883 » Wed Dec 27, 2017 11:07 am

Thanks to all.

Mark, I have only the BF of the Quark. It works fine with my Lunt with no unevennes in the images, but I don't have a separate barrel to use it without the Quark, and this prevents making FD images. I am planning to purchase a larger one from Andover together with a T-mount barrel from Edmund Optics.
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