Page 1 of 1

Solar granulation and Ha 15th July

Posted: Sun Jul 15, 2018 3:53 pm
by Carbon60
I rolled out the 250mm RCT this morning although the conditions were not good wrt seeing and the SER video files were quite a mess. Even with 2x2 binning, shortening the exposure time to 0.8 ms to maximise the chances of freezing the turbulence, I struggled to capture anything really 'solid' for Imppg to process and the end results are a bit soft.

Lunt 35mm Etalon
Basler acA1920-155um camera
TV Powermate 2.5x
Genika Astro image capture (60 seconds at 0.8ms)
AS!3 (1% of 9982 frames)
Imppg
PixInsight

Image20180715_AR_250RCT_mono by Stuart Green, on Flickr

Image20180715_AR_250RCT_colour by Stuart Green, on Flickr

I then moved on to capture an image of solar granulation using a broadband (7nm red Ha filter). Pity there are no sunspots.

Image20180715_Granulation_mono by Stuart Green, on Flickr

Image20180715_Granulation_colour by Stuart Green, on Flickr

Thanks for looking.

Stu.

Re: Solar granulation and Ha 15th July

Posted: Sun Jul 15, 2018 6:11 pm
by Valery
Very nice images taken into account such a seeing.

Better luck with a good seeing is what we all need first of all.


Valery

Re: Solar granulation and Ha 15th July

Posted: Mon Jul 16, 2018 12:25 am
by ffellah
I love those granulation shots, Stu

Franco

Re: Solar granulation and Ha 15th July

Posted: Mon Jul 16, 2018 12:46 am
by MapleRidge
Hi Stu...

Good images despite the seeing.

The granulation worked out best, just wondered if the Ha and WL are the same image scale?

Brian

Re: Solar granulation and Ha 15th July

Posted: Mon Jul 16, 2018 5:03 am
by marktownley
They came out well Stu, my seeing was shot most of the time. 50mm was about my limit...

Re: Solar granulation and Ha 15th July

Posted: Mon Jul 16, 2018 7:29 am
by Valery
Stue,

I looked at my yesterday's H-a images I see that I do use smaller scale than you do, while my telescope is 110% in size. I think you will get better results with somewhat smaller scale at the camera chip. This will makes your H-a images sharper and better looking. Not say about shorter exposures, shorter cadence of the movies, better atmosphere freezing.

When my seeing is not exellent, I always make the scale 30% smaller and this really helps.


Valery

Re: Solar granulation and Ha 15th July

Posted: Mon Jul 16, 2018 10:39 am
by Montana
These are great Stu! :bow no chance for solar for me this weekend as I was so busy with chores and visiting friends. Hope you had a lovely holiday :)
Alexandra

Re: Solar granulation and Ha 15th July

Posted: Mon Jul 16, 2018 2:48 pm
by pedro
Great HR images Stu

Re: Solar granulation and Ha 15th July

Posted: Mon Jul 16, 2018 6:26 pm
by p_zetner
Love the granulation images. Looks like seeing was fighting against you for the H alpha.
Cheers, peter.

Re: Solar granulation and Ha 15th July

Posted: Thu Jul 19, 2018 5:55 am
by Carbon60
Valery wrote: Mon Jul 16, 2018 7:29 am Stue,

I looked at my yesterday's H-a images I see that I do use smaller scale than you do, while my telescope is 110% in size. I think you will get better results with somewhat smaller scale at the camera chip. This will makes your H-a images sharper and better looking. Not say about shorter exposures, shorter cadence of the movies, better atmosphere freezing.

When my seeing is not exellent, I always make the scale 30% smaller and this really helps.


Valery
Many thanks for the advice, Valery.

Stu.

Re: Solar granulation and Ha 15th July

Posted: Thu Jul 19, 2018 5:56 am
by Carbon60
Many thanks for your kind feedback everyone.

Stu.

Re: Solar granulation and Ha 15th July

Posted: Thu Jul 19, 2018 4:03 pm
by Ewan
The WL shots came out very clean Stu, I must try my Ha 7nm with the SCT now ;-) , 60 seconds is a long time for a capture though, won't you end up with a lot of frames that have movement thus reducing the amount of best 'the same detail' frames to stack Stu ? just a thought.

I have found that you don't always need a very quick capture rate, 6Ms is my normal 'speed' but 8Ms - 12Ms also give great results & I never capture in 8Bit anymore ;-)

Re: Solar granulation and Ha 15th July

Posted: Thu Jul 19, 2018 8:27 pm
by allhoest
Even for difficult seeing condition, the details of the chromosphere are well impressive.
I like the granulation too.
CS
Alex