Fabulous results!

The H beta looks good and it’s great to see the HeD3.

Thanks for your comments, Mark and Alexandra. There's actually some interesting information hidden in the animations. If you look at features in the red and blue wings of the H alpha line (symmetrically spaced around line centre) they are actually quite different. This is because of their motions an...

Here is a cropped version showing only the active region.

Hi Everyone. Part of my June 23 spectroheliography session was devoted to experimenting with a barlow on the telescope (C4 NexStar with Celestron barlow) for a more magnified image scale. At first, I didn't think much of the results because of severe vignetting with the barlow. On closer inspection,...

Thanks for the feedback Alexandra, Mark and Stu.
Alexandra, I will work on a better graphic to help explain the observations and post it as soon as I get the chance.
Cheers.
Peter

Nice results, John.

Hi John.
I’m assuming this is an animation of two spectroheliograms?
Are they generated from the same video or two different videos?
Peter

Hi Everyone. I posted a few images previously from my 23 May spectroheliography session: https://solarchatforum.com/viewtopic.php?t=36323 Here are a few more spectroheliograms as well as some spectra. UV_montage_siz.jpg UV_Spectrum_montage_siz.jpg The measured spectra agree well with the BASS2000 sp...

Thanks, Fulvio.
All the best.
Peter

Hi Everyone. Warren's spectacular animation of the huge NW filaprom on the 23rd showed a lot of complex motion. https://solarchatforum.com/viewtopic.php?t=36774 Since I was imaging with my SHG on the same day, I thought I would take a look at the prominence spectrum to see if there was any sign of i...

Thanks for your kind comments Alan, Alexandra and mark.
Cheers.
Peter

Hi Alexandra. You might be referring to the BASS2000 website? Here’s the link: https://bass2000.obspm.fr/solar_spect.php The BASS2000 spectrum isn’t labelled but there is an associated downloadable pdf with all the lines identified. There’s also the Liege solar spectrum atlas to play with: https://f...

Terrific animation!
The southernmost part sure does look like a monstrous twister.
Cheers.
Peter

Hi. The most exhaustive data base I know is that of the American National Institute of Standards and Technology (NIST). A good starting point for you would be the “Basic Atomic Spectroscopic Data” page at https://physics.nist.gov/PhysRefData/Handbook/element_name.htm Click on the element you’re inte...

Hello Everyone. Here is a collection of images from my spectroheliography session of 23 June. The montage shows three chromospheres (hydrogen, calcium and helium) in four lights: Ca H (396.85 nm), H beta (486.13 nm), He D3 (587.56 nm) and H alpha (656.28 nm). These are the Fraunhofer H, F, D3 and C ...

These are excellent!
I’m a little surprised that you claim a spectral resolution of 0.16 angstroms. How did you measure this?

Your raw data is remarkably clean! There is always a characteristic “spiky” appearance to features I capture in my spectroheliograms. I assume this is due to seeing variations over the course of my (slow) scan. What surprises me is that these spiky variations don’t seem to appear in your raw (fast) ...

Thanks Chris and Alexandra.

I thought I would post another Ca H image processed to preserve the prominences.
There's a filaprom visible on the E side of the Northern pole which was lost in my previous processing of the disk.

Cheers.
Peter

These are very nice results. I have to admit I'm surprised at the better definiton you achieve with the 600 l/mm grating. You're also able to capture quite a wide field of view with this grating. I would have thought that you are beginning to shift too far away from the absorption line centre at the...

These are very good!
I certainly agree that, apart from H alpha, "filaments only appear clearly with quite narrowband imaging".
Your results are making wonder if I should give the "fast scan" technique a try!
Cheers.
Peter

Hello Everyone. I've been very slow to process data but have finally prepared the next installment of images from my 22May spectroheliography session. The montage below shows four different views of the solar chromosphere in the lights of Ca H (396.85 nm), H beta (486.13 nm), He D3 (587.56 nm) and H...

That’s a very nice result.
Well done.
Peter

Hi Everyone. I've been slow to process images but wanted to amend the original post which shows H alpha disks at (presumed) line centre and in the red wing. When I processed blue wing images, it became evident that my wavelength calibration was off. So, here are H alpha spectroheliograms in both red...

This looks very promising!
Thanks for pursuing this.
Cheers.
Peter