Search found 987 matches

by p_zetner
Sat Oct 13, 2018 6:15 pm
Forum: Solar Radio, Magnetometry and Spectroscopy
Topic: For Science / Math Lovers: Measurement of a Solar Filament Temperature.
Replies: 6
Views: 3112

For Science / Math Lovers: Measurement of a Solar Filament Temperature.

Hi Everyone. In my last imaging session with the spectroheliograph, I observed a strong filament in both the H alpha and Ca K images. Here are two images with the filament at, roughly, the solar equator towards the E limb chosen to be the one for study. Montage_Finals_Ha-CaK lvls siz.png An interest...
by p_zetner
Mon Oct 08, 2018 3:36 pm
Forum: This is SolarChat !!
Topic: Today's SUN (20181006) | low activity
Replies: 9
Views: 955

Re: Today's SUN (20181006) | low activity

Another nice set of images, Pedro.
The H alpha proms add some beautiful detail.

Cheers.
Peter
by p_zetner
Mon Oct 08, 2018 3:33 pm
Forum: This is SolarChat !!
Topic: Gorgeous Prom Groups Today, HA 120mm, Oct 7th 2018
Replies: 10
Views: 1207

Re: Gorgeous Prom Groups Today, HA 120mm, Oct 7th 2018

Nicely done, Marty.

Cheers.
Peter
by p_zetner
Mon Oct 08, 2018 3:33 pm
Forum: SPoD Archive
Topic: Gorgeous Prom Groups Today, HA 120mm, Oct 7th 2018
Replies: 10
Views: 2266

Re: Gorgeous Prom Groups Today, HA 120mm, Oct 7th 2018

Nicely done, Marty.

Cheers.
Peter
by p_zetner
Mon Oct 08, 2018 3:32 pm
Forum: Solar Radio, Magnetometry and Spectroscopy
Topic: Weekend Geomagnetic Storm UPDATED 7th & 9th Oct. 18
Replies: 3
Views: 2079

Re: Weekend Geomagnetic Storm 7th & 8th Oct. 18

Hi Stu.

Saw the SDO image of the large coronal hole on Spaceweather a couple of days ago and was anticipating your report.
Sure enough .... !

Cheers.
Peter
by p_zetner
Mon Oct 08, 2018 3:28 pm
Forum: This is SolarChat !!
Topic: Sharpening high resolution CaK images
Replies: 17
Views: 2123

Re: Sharpening high resolution CaK images

I’m really enjoying this thread!

Christian, I’ve placed my pre-order for your book.

Cheers.
Peter
by p_zetner
Fri Oct 05, 2018 3:44 pm
Forum: Solar Reference Library
Topic: For Daystar CaH quark owners
Replies: 4
Views: 3951

Re: For Daystar CaH quark owners

Just an observation that the results published in this paper were captured at a spectral resolving power of 850000 ! That’s a fwhm bandpass of about 0.005 Angstroms (5 milliAngstroms) at this spectral line. It doesn’t seem to be necessary to use such high resolving power. But, if you look at figure ...
by p_zetner
Fri Oct 05, 2018 12:57 am
Forum: Solar Reference Library
Topic: For Daystar CaH quark owners
Replies: 4
Views: 3951

Re: For Daystar CaH quark owners

Very much an interesting idea for “spectroheliographers” ! I’m going to be concentrating on the blue portion of the spectrum with higher spectral resolution. I’d be interested (and able) to catch these emission events. Thanks for the reference.

Cheers.
Peter
by p_zetner
Mon Oct 01, 2018 11:49 pm
Forum: This is SolarChat !!
Topic: Sharpening high resolution CaK images
Replies: 17
Views: 2123

Re: Sharpening high resolution CaK images

Hi Frank. My guess would be that the DOT images you have posted have not had much, if any, processing applied to them. I'd say that most digital images, especially when oversampled, contain underlying details that can be made visible by deconvolution and / or sharpening. If you look at two of the sc...
by p_zetner
Mon Oct 01, 2018 4:59 pm
Forum: Solar Scope Modifications
Topic: Details of a telecentric lens for C8 Edge and Daystar filter
Replies: 10
Views: 3751

Re: Details of a telecentric lens for C8 Edge and Daystar filter

Hi Bob. Here is an analysis of my ~ 4.5X telecentric used with a "classic" (non-Edge) C8 scope. The scope model comes from Ed Moreno and is attributed to Ken Hutchinson. The performance at f46 looks to be diffraction limited for hydrogen alpha and a sensor diagonal of 14mm. I've also introduced a fo...
by p_zetner
Sun Sep 30, 2018 6:23 pm
Forum: This is SolarChat !!
Topic: SunSpot 2723 (Animated!), Proms, 120mm HA | Sept 30th 2018
Replies: 12
Views: 1120

Re: SunSpot 2723 (Animated!), Proms, 120mm HA | Sept 30th 2018

Another nice set of images, Marty.
That animation is terrific saw well.

Cheers.
Peter
by p_zetner
Sun Sep 30, 2018 6:20 pm
Forum: This is SolarChat !!
Topic: AR2723 September 30th
Replies: 16
Views: 1461

Re: AR2723 September 30th

What a beautiful little dipole!

Well done, Franco. Nice image.

Cheers.
Peter
by p_zetner
Sun Sep 30, 2018 6:20 pm
Forum: SPoD Archive
Topic: AR2723 September 30th
Replies: 7
Views: 1891

Re: AR2723 September 30th

What a beautiful little dipole!

Well done, Franco. Nice image.

Cheers.
Peter
by p_zetner
Fri Sep 28, 2018 11:40 pm
Forum: This is SolarChat !!
Topic: Lunt calcium filter imaging thread
Replies: 18
Views: 2215

Re: Lunt calcium filter imaging thread

Here are older images taken of the full disk, an AR closeup and proms (with inverted disk). All were taken with Lunt B1800. All except the full disk had the Lunt stacked with an Omega 2 Angstrom (nominally) filter. Possibly a contrast improvement ... not sure and didn't really carry out study with /...
by p_zetner
Mon Sep 17, 2018 1:55 am
Forum: This is SolarChat !!
Topic: Chromosphere September 16th
Replies: 13
Views: 1388

Re: Chromosphere September 16th

Very nice images, Franco.
I guess we’re stuck with small ARs for a while!
Cheers.
Peter
by p_zetner
Sun Sep 16, 2018 9:00 pm
Forum: This is SolarChat !!
Topic: Prominence Hedgerow Animation
Replies: 12
Views: 1422

Re: Prominence Hedgerow Animation

Beautiful animation!

Cheers.
Peter
by p_zetner
Sun Sep 16, 2018 6:19 pm
Forum: Solar Reference Library
Topic: Surface contrast in CaK for various filter bandpasses.
Replies: 16
Views: 3690

Re: Surface contrast in CaK for various filter bandpasses.

Thanks for your comments Eric, George and Mark. George, I really appreciate your feedback on this. I am planning to do a similar filter simulation for the H alpha sweep. A direct comparison of the CaK and H alpha simulations will, I'm sure, confirm what you have concluded in your comparison of the s...
by p_zetner
Sat Sep 15, 2018 4:32 pm
Forum: Solar Radio, Magnetometry and Spectroscopy
Topic: 08Aug: Spectral sweep through the Ca K line
Replies: 13
Views: 3627

Re: 08Aug: Spectral sweep through the Ca K line

Thanks, John.

As you can imagine, these animations require a lot of work (40 spectroheliograms in this case) but I enjoy the end result.

Cheers.
Peter
by p_zetner
Sat Sep 15, 2018 4:28 pm
Forum: This is SolarChat !!
Topic: September 13 in Ha
Replies: 12
Views: 1356

Re: September 13 in Ha

Nice images, Brian.
You captured some pretty fine detail in those proms.

Cheers.
Peter
by p_zetner
Sat Sep 15, 2018 3:58 pm
Forum: Solar Reference Library
Topic: Surface contrast in CaK for various filter bandpasses.
Replies: 16
Views: 3690

Re: Surface contrast in CaK for various filter bandpasses.

Thanks for the comments everyone. One thing I wanted to note was that my simulated filter (spectral) transmission curve is Gaussian while an etalon filter (single stack) has a Lorentzian profile. The Lorentzian curve has broader shoulders ( https://solarchatforum.com/viewtopic.php?f=8&t=22830 ) so t...
by p_zetner
Fri Sep 14, 2018 8:14 pm
Forum: Solar Reference Library
Topic: Surface contrast in CaK for various filter bandpasses.
Replies: 16
Views: 3690

Surface contrast in CaK for various filter bandpasses.

Hello Everyone. I recently posted an animated spectral sweep through the CaK assembled from images taken with my spectroheliograph on Aug08. https://solarchatforum.com/viewtopic.php?f=8&t=25028 It brought up some interesting questions from Valery and Christian that I thought I'd look into. The basic...
by p_zetner
Fri Sep 14, 2018 1:54 pm
Forum: This is SolarChat !!
Topic: Tiny AR12721 in H-alpha and CaK: Sept10
Replies: 7
Views: 871

Re: Tiny AR12721 in H-alpha and CaK: Sept10

Thanks, Everyone.

Raf, I'm very pleased with the uv performance of this scope. It's time to adjust the optics and push the magnification a little bit!

Cheers.
Peter
by p_zetner
Thu Sep 13, 2018 10:09 pm
Forum: Solar Radio, Magnetometry and Spectroscopy
Topic: 08Aug: Spectral sweep through the Ca K line
Replies: 13
Views: 3627

Re: 08Aug: Spectral sweep through the Ca K line

Ken: Thanks for running the calculation. It seems to be in the ball park, although, I guess, it is a best estimate of resolution as, for example, optical aberrations aren't considered. It's pure laziness that I haven't made a bench test of the resolution recently. I'll do this in the near future. Va...
by p_zetner
Thu Sep 13, 2018 10:00 pm
Forum: Solar Radio, Magnetometry and Spectroscopy
Topic: G2 Geomagnetic Storm 11th Sept 2018
Replies: 5
Views: 2225

Re: G2 Geomagnetic Storm 11th Sept 2018

Nice recording, Stu.
It strikes me as odd and interesting that you're measuring this kind of activity with the quiet Sun. I would've thought there's more of a connection with magnetic activity.

Cheers.
Peter
by p_zetner
Thu Sep 13, 2018 9:19 pm
Forum: This is SolarChat !!
Topic: Tiny AR12721 in H-alpha and CaK: Sept10
Replies: 7
Views: 871

Tiny AR12721 in H-alpha and CaK: Sept10

Hi Everyone. Seeing was bad to mediocre and definitely affected the quality of the higher res h-alpha images here. The CaK didn't turn out too badly. The highest res h-alpha was 2x2 binned at capture (shorter exposure time allowed). Cheers. Peter 2018-09-10-090139-0000_proc1_crop_png-proc.png 2018-0...