Corona versus insect

this is the main message area for anything solar :)
Post Reply
george9
Im an EXPERT!
Im an EXPERT!
Posts: 346
Joined: Tue Jan 26, 2016 1:28 am
Has thanked: 159 times
Been thanked: 400 times

Corona versus insect

Post by george9 »

i went to Utsayantha Mountain on Oct 1 and was shooting the corona. In between my on-band shot and my off-band shot, an insect laid a gossamer thread across the dew shield in front of the objective. It was too thin to see normally, but it glinted for a moment when I was taking down the scope at the end of the session. The result was this glow from 5 to 11 o'clock with a sharp edge toward the bottom of the image.

Hripcsak 2023-10-01-1454_9-CapObj_____100r_48T_46reg rot contrast.jpg
Hripcsak 2023-10-01-1454_9-CapObj_____100r_48T_46reg rot contrast.jpg (56.86 KiB) Viewed 1448 times


As a result, I could not subtract these two images from each other:

Hripcsak 2023-10-01-1436_5-CapObj_____100r_48T_46reg rot.jpg
Hripcsak 2023-10-01-1436_5-CapObj_____100r_48T_46reg rot.jpg (237.76 KiB) Viewed 1448 times
Hripcsak 2023-10-01-1454_9-CapObj_____100r_48T_46reg rot.jpg
Hripcsak 2023-10-01-1454_9-CapObj_____100r_48T_46reg rot.jpg (237.45 KiB) Viewed 1448 times


So instead I did the best I could with a single on-band stack. While it doesn't reach the dim corona that it ought to, I think it has higher resolution. I suspect I need to work on my subtraction processing.

Hripcsak 2023-10-01-1436_5-CapObj_____100r_48T_46reg_adjust sharpen.jpg
Hripcsak 2023-10-01-1436_5-CapObj_____100r_48T_46reg_adjust sharpen.jpg (189.5 KiB) Viewed 1448 times


And here is the satellite image:
SDO 20231001_142923_4096_0211 circle.jpg
SDO 20231001_142923_4096_0211 circle.jpg (247.93 KiB) Viewed 1448 times


George


User avatar
DeepSolar64
Way More Fun to Share It!!
Way More Fun to Share It!!
Posts: 18534
Joined: Thu Sep 05, 2019 12:19 am
Location: Lowndesville S.C.
Has thanked: 17256 times
Been thanked: 16319 times

Re: Corona versus insect

Post by DeepSolar64 »

George,
I didn’t know you were using a tunable filter. It must be of a very narrow bandpass. I know professionals use green wavelength filters for coronagraphy. What wavelength is it? 530nm?

These look really nice. You are one of a very few that can view the corona without a solar eclipse!

James.


Lunt 8x32 SUNoculars
Orion 70mm Solar Telescope
Celestron AstroMaster Alt/Az Mount
Meade Coronado SolarMax II 60 DS
Meade Coronado SolarMax II 90 DS
Meade Coronado AZS Alt/Az Mount
Astro-Tech AT72EDII with Altair solar wedge
Celestron NexStar 102GT with Altair solar wedge
Losmandy AZ8 Alt/Az Mount
Sky-Watcher AZGTI Alt-Az GoTo mount
Cameras: ZWO ASI178MM, PGR Grasshopper, PGR Flea
Lunt, Coronado, TeleVue, Orion and Meade eyepieces

Image Visual Observer
" Way more fun to see it! "
User avatar
marktownley
Librarian
Librarian
Posts: 41923
Joined: Tue Oct 18, 2011 5:27 pm
Location: Brierley Hills, UK
Has thanked: 19936 times
Been thanked: 9926 times
Contact:

Re: Corona versus insect

Post by marktownley »

Brilliant thanks George, amazing the scattering effect of that thread.


Image
http://brierleyhillsolar.blogspot.co.uk/
Solar images, a collection of all the most up to date live solar data on the web, imaging & processing tutorials - please take a look!
User avatar
Montana
Librarian
Librarian
Posts: 34411
Joined: Mon Oct 17, 2011 5:25 pm
Location: Cheshire, UK
Has thanked: 17265 times
Been thanked: 8671 times

Re: Corona versus insect

Post by Montana »

Every time I see these images I find them incredible :bow :bow :bow

Alexandra


User avatar
DeepSolar64
Way More Fun to Share It!!
Way More Fun to Share It!!
Posts: 18534
Joined: Thu Sep 05, 2019 12:19 am
Location: Lowndesville S.C.
Has thanked: 17256 times
Been thanked: 16319 times

Re: Corona versus insect

Post by DeepSolar64 »

Alexandra,
So do I. George and Klaus should be an inspiration to all of us to do coronagraphy if possible. It's a facet of amateur solar astronomy that few even attempt, much less succeed at. I am talking about true corona here. Not coronagraph style prominence viewers. Unfortunately many of us do not have dry deep blue skies which this requires.

And if they were only a commercially made true coronagraph available. Or an available kit like the Sol-Ex.

James


Lunt 8x32 SUNoculars
Orion 70mm Solar Telescope
Celestron AstroMaster Alt/Az Mount
Meade Coronado SolarMax II 60 DS
Meade Coronado SolarMax II 90 DS
Meade Coronado AZS Alt/Az Mount
Astro-Tech AT72EDII with Altair solar wedge
Celestron NexStar 102GT with Altair solar wedge
Losmandy AZ8 Alt/Az Mount
Sky-Watcher AZGTI Alt-Az GoTo mount
Cameras: ZWO ASI178MM, PGR Grasshopper, PGR Flea
Lunt, Coronado, TeleVue, Orion and Meade eyepieces

Image Visual Observer
" Way more fun to see it! "
User avatar
arnedanielsen
Way More Fun to Share It!!
Way More Fun to Share It!!
Posts: 7055
Joined: Fri Apr 18, 2014 10:42 pm
Location: Vestby, Norway
Has thanked: 6004 times
Been thanked: 6881 times

Re: Corona versus insect

Post by arnedanielsen »

Very impressive results George!


Best regards,
Arne
--
AstroBin: https://www.astrobin.com/users/arnedani/
george9
Im an EXPERT!
Im an EXPERT!
Posts: 346
Joined: Tue Jan 26, 2016 1:28 am
Has thanked: 159 times
Been thanked: 400 times

Re: Corona versus insect

Post by george9 »

Thanks, all.

James, yes, that is 5303A for Fe XIV. The FWHM is about 1.2A by using two 2A filters. It is slightly tunable in the sense that if I drop the temperature by over 12C, it goes off band. 20C is pretty much completely off band. At 12C it is far enough to use as a negative image.

On the skies, yes you need to occasionally have blue skies, either in your backyard or by driving somewhere. Keep in mind, though, that I have gotten the corona from the Peconic Bay on Long Island, NY. It's not known for deep blue skies, and it is at sea level. Connecticut can be humid and hazy, and I got pretty good images this summer.

George


Post Reply