Jump to content

  •  

CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.

Photo

Solar granulation with the 300 mm solar scope : from red to violet light (G band)

  • Please log in to reply
6 replies to this topic

#1 ch-viladrich

ch-viladrich

    Viking 1

  • -----
  • topic starter
  • Posts: 601
  • Joined: 14 Jul 2013
  • Loc: France

Posted 09 July 2018 - 01:58 PM

Dear All,

 

I has been nearly one year since the last time I use my 300 mm solar telescope.

Last Saturday morning, the conditions were not very promising. The wind came from North-West, which usually is not good for the seeing. Furthemore the sky was coronal, which is not good either. On top of that there was not a single spot or even a small pore in view.

Having re-collimated the scope during the previous night, I decided to give it a try anyway just to check out my collimation on the Sun.

I started with a red filter (656 nm), then switch to a green filter (540 nm), to a blue/green filter (500 nm) and finally to the 430 nm (G band filter).

This sequence shows the increase of contrast and resolution when going from red to blue light.

 

Here are the images.

 

Red light (656 nm), the contrast is rather low :

Granulation-7july2018-9h41mnUT-N300-656n

 

Green light (540 nm), the contrast is much better :

Granulation-7July2018-9h52mnUT-N300-540n

 

Green/blue light filter (500 nm). This is usually the optimum filter for my observing site :

granulation-7July2018-10h24mnUT-N300-500

 

 

G band (430 nm). This filter bring us in a different world, with intergranular bright spots and filigrees becoming visible :

granulation-7July2018-10h58mnUT-N300-430

Best regards

Christian Viladrich


  • BYoesle, Paul Hyndman, George Bailey and 12 others like this

#2 MalVeauX

MalVeauX

    Cosmos

  • *****
  • Posts: 7,976
  • Joined: 25 Feb 2016
  • Loc: Florida

Posted 09 July 2018 - 04:04 PM

Awesome comparison Christian! Great captures!

 

Which 430nm filter are you using?

 

Very best,



#3 ch-viladrich

ch-viladrich

    Viking 1

  • -----
  • topic starter
  • Posts: 601
  • Joined: 14 Jul 2013
  • Loc: France

Posted 09 July 2018 - 04:11 PM

Thanks Marty smile.gif

This is an Andover filter, 430.5 nm CWL and 1.9 nm FWHM. You can find it near the middle of this web page :

https://www.andoverc...ndpass-filters/


  • MalVeauX likes this

#4 Dave LoPresti

Dave LoPresti

    Vanguard

  • -----
  • Posts: 2,004
  • Joined: 25 Dec 2003
  • Loc: Preston, Connecticut

Posted 09 July 2018 - 07:20 PM

That's nice work, Christian. I really like this. It's great to see the comparison like that. G-band gets my vote as the coolest.

 

I guess your collimation is ok..cool.gif



#5 MalVeauX

MalVeauX

    Cosmos

  • *****
  • Posts: 7,976
  • Joined: 25 Feb 2016
  • Loc: Florida

Posted 09 July 2018 - 07:46 PM

Thanks Marty smile.gif

This is an Andover filter, 430.5 nm CWL and 1.9 nm FWHM. You can find it near the middle of this web page :

https://www.andoverc...ndpass-filters/

Thanks, interesting!

 

Very best,



#6 soldatispace

soldatispace

    Vostok 1

  • -----
  • Posts: 185
  • Joined: 20 Apr 2011
  • Loc: Fribourg, Switzerland

Posted 30 July 2018 - 11:12 AM

Hello Christian,

Great comparison! Thank you for sharing!

Kind regards,
Nicolas

Edited by soldatispace, 30 July 2018 - 11:14 AM.


#7 ch-viladrich

ch-viladrich

    Viking 1

  • -----
  • topic starter
  • Posts: 601
  • Joined: 14 Jul 2013
  • Loc: France

Posted 05 August 2018 - 02:48 PM

Thanks guys :-)




CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.


Recent Topics






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics