Search found 1163 matches

by p_zetner
Mon Mar 01, 2021 4:56 am
Forum: Solar Radio, Magnetometry and Spectroscopy
Topic: Zeeman effect in mercury using the home-made Fabry-Perot (with gifs!)
Replies: 3
Views: 51

Re: Zeeman effect in mercury using the home-made Fabry-Perot (with gifs!)

Wonderful stuff! What a bonanza of results. Where to go from here? It would be interesting to plot out a few of these interferograms and see how well the observed Zeeman pattern matches the theory. The green and yellow Hg patterns seem especially sharp in the gif. Do you have full resolution image f...
by p_zetner
Sun Feb 28, 2021 9:14 pm
Forum: Solar Radio, Magnetometry and Spectroscopy
Topic: Testing a Daystar QPE 0.6A filter with a H spectrum tube.
Replies: 4
Views: 107

Testing a Daystar QPE 0.6A filter with a H spectrum tube.

Hello Everyone. To look further into etalon testing methods, I applied the scheme used for the Lunt etalon to my Daystar QPE0.6A filter. The two parameters I was able to measure are the wavelength readout calibration and the fwhm bandpass. The integral blocking filter makes it impossible (?) to meas...
by p_zetner
Sat Feb 27, 2021 10:23 pm
Forum: Solar Scope Modifications
Topic: Sweet spot, banding and tilted etalons ...where are the limits ?
Replies: 49
Views: 626

Re: Sweet spot, banding and tilted etalons ...where are the limits ?

Hi Christian. I'm assuming banding wouldn't be an issue for etalons that are tuned slightly to the red for normal incidence? Here is a series of interferograms taken in H alpha (discharge tube + 10nm fwhm interference filter) for the Lunt LS50FHa etalon. Montage_131626-742-821_levels.jpg From left t...
by p_zetner
Sat Feb 27, 2021 3:31 am
Forum: This is SolarChat !!
Topic: Sun in Ha, CaK and WL 26th Feb 2021
Replies: 8
Views: 69

Re: Sun in Ha, CaK and WL 26th Feb 2021

Lovely series, Stu, particularly the close up H alpha.
Cheers.
Peter
by p_zetner
Sat Feb 27, 2021 3:29 am
Forum: This is SolarChat !!
Topic: AR2804 in High Res | Feb 26th 2021
Replies: 19
Views: 182

Re: AR2804 in High Res | Feb 26th 2021

Another great series of “stellar” solar shots, Marty!
Thanks for sharing and I’m always impressed by your sage advice on imaging techniques.
Cheers.
Peter
by p_zetner
Fri Feb 26, 2021 12:12 am
Forum: This is SolarChat !!
Topic: h-alpha and CaK, February 24th, 2021
Replies: 11
Views: 101

Re: h-alpha and CaK, February 24th, 2021

Beautiful shots Frank!
Your full disks have great uniformity across the field of view and that prom is spectacular.
Cheers.
Peter
by p_zetner
Fri Feb 26, 2021 12:10 am
Forum: This is SolarChat !!
Topic: Sony starvis- aca3088-57um first light
Replies: 5
Views: 81

Re: Sony starvis- aca3088-57um first light

An interesting camera. Thanks for posting.
Cheers.
Peter
by p_zetner
Fri Feb 26, 2021 12:07 am
Forum: This is SolarChat !!
Topic: Solar Images from Daystar Gemini
Replies: 17
Views: 264

Re: Solar Images from Daystar Gemini

Wow! These are spectacular!
Well done.
Cheers.
Peter
by p_zetner
Thu Feb 25, 2021 10:08 pm
Forum: Solar Radio, Magnetometry and Spectroscopy
Topic: Testing a Lunt LS50FHa etalon with a H spectrum tube.
Replies: 14
Views: 428

Re: Testing a Lunt LS50FHa etalon with a H spectrum tube.

Hi Christian. A factor of two in the fwhm bothers me a little but not too much because this is dependent on a measurement of the fringe width which depends on image sharpness and hence camera lens quality and f ratio. At least I can understand how a discrepancy between my measured fwhm of 1.6 angstr...
by p_zetner
Wed Feb 24, 2021 7:38 pm
Forum: Solar Radio, Magnetometry and Spectroscopy
Topic: Testing a Lunt LS50FHa etalon with a H spectrum tube.
Replies: 14
Views: 428

Re: Testing a Lunt LS50FHa etalon with a H spectrum tube.

Thanks everyone for the thoughtful feedback. Christian: Your points are well taken. Concerning your comment if you take into account the lens focal length, then you can calculate the FWHM (and FSR) in Angstrom I'd like to demonstrate a method that doesn't require knowledge of the camera lens focal l...
by p_zetner
Mon Feb 22, 2021 11:33 pm
Forum: Solar Radio, Magnetometry and Spectroscopy
Topic: Testing a Lunt LS50FHa etalon with a H spectrum tube.
Replies: 14
Views: 428

Testing a Lunt LS50FHa etalon with a H spectrum tube.

Hello Everyone. Inspired by the Zoom meeting yesterday, I thought I would make an attempt at etalon testing using a discharge tube lamp. Here are my preliminary results investigating a Lunt LS50FHa etalon. The setup is the same as that described by Christian in this thread: https://solarchatforum.co...
by p_zetner
Sun Feb 21, 2021 8:23 pm
Forum: This is SolarChat !!
Topic: Zoom Meeting - 21 February @ 18:00 UT
Replies: 74
Views: 1477

Re: Zoom Meeting - 21 February @ 18:00 UT

Thanks all for an enjoyable discussion and thanks to Brian and Alexandra for organizing.
Cheers.
Peter
by p_zetner
Sat Feb 20, 2021 6:35 pm
Forum: Solar Radio, Magnetometry and Spectroscopy
Topic: A New Spectroheliograph
Replies: 10
Views: 265

Re: A New Spectroheliograph

Thanks for the feedback, everyone Stuart: I'll agree that slits are a problem. The bands you see ("transversalium") running along the grating dispersion direction (orthogonal to the spectral lines) are indeed due to dust and irregularities at the slit opening. Would razor blades be a better choice t...
by p_zetner
Fri Feb 19, 2021 11:50 pm
Forum: Solar Radio, Magnetometry and Spectroscopy
Topic: A New Spectroheliograph
Replies: 10
Views: 265

A New Spectroheliograph

Hello Everyone. I've constructed a second spectroheliograph and thought I'd post some of the details. Why a second SHG do you ask? I'm modifying the 1st one to give me significantly better spectral resolution (bandpass < 0.1 angstroms) in order to study narrower solar lines. My first experiments wit...
by p_zetner
Wed Feb 17, 2021 4:03 pm
Forum: Solar Radio, Magnetometry and Spectroscopy
Topic: Fabry-Perot etalon testing: Zeeman splitting of neon
Replies: 14
Views: 338

Re: Fabry-Perot etalon testing: Zeeman splitting of neon

I’d like to make some concluding comments about my rough analysis of the interferograms posted in this thread and suggest an analysis procedure one might want to consider for future measurements of this type. Using the etalon spacing, as I did in this analysis, is a poor method but was used because ...
by p_zetner
Tue Feb 16, 2021 12:46 am
Forum: Solar Radio, Magnetometry and Spectroscopy
Topic: Fabry-Perot etalon testing: Zeeman splitting of neon
Replies: 14
Views: 338

Re: Fabry-Perot etalon testing: Zeeman splitting of neon

Sounds like a terrific program of experiments! I like the idea of looking at the splitting in the longitudinal direction. In principle, you would then have a known sense of circular polarization available with which you could calibrate the sense of a circular polarizer, something very difficult to d...
by p_zetner
Mon Feb 15, 2021 5:47 pm
Forum: Solar Radio, Magnetometry and Spectroscopy
Topic: Fabry-Perot etalon testing: Zeeman splitting of neon
Replies: 14
Views: 338

Re: Fabry-Perot etalon testing: Zeeman splitting of neon

To thesmiths: I've calculated some results for your Zeeman effect experiment. They are all based on the value of the etalon cavity spacing which I chose to be 3.25mm according to the information you supplied and a source wavelength of 653.3nm. As we've discussed and as Christian has emphasized, this...
by p_zetner
Sun Feb 14, 2021 6:49 pm
Forum: Solar Radio, Magnetometry and Spectroscopy
Topic: Fabry-Perot etalon testing: Zeeman splitting of neon
Replies: 14
Views: 338

Re: Fabry-Perot etalon testing: Zeeman splitting of neon

I couldn't resist an attempt to analyze your interferograms! Here is the sigma polarization image showing a line along which I plotted intensities (ImageJ) and the plotted intensities. (Edit Feb15: Ooops. This is the pi interferogram but the line used for plotting was identical and the plotted resul...
by p_zetner
Sat Feb 13, 2021 8:38 pm
Forum: This is SolarChat !!
Topic: Zoom Meeting - 21 February @ 18:00 UT
Replies: 74
Views: 1477

Re: Interest in a Zoom Meeting?

I’m hoping I can make it. Please count me in!
Cheers.
Peter
by p_zetner
Sat Feb 13, 2021 3:45 pm
Forum: Solar Radio, Magnetometry and Spectroscopy
Topic: Fabry-Perot etalon testing: Zeeman splitting of neon
Replies: 14
Views: 338

Re: Fabry-Perot etalon testing: Zeeman splitting of neon

Hi. I was thinking you would use the observed line splitting to measure the field. I’ve attached a useful formula. You measure the sigma components with polarizer perpendicular to the field and pi component with polarizer parallel to the field. Cheers. Peter 808479B5-8054-41B1-A936-A0558E762447.png
by p_zetner
Sat Feb 13, 2021 4:13 am
Forum: Solar Radio, Magnetometry and Spectroscopy
Topic: Fabry-Perot etalon testing: Zeeman splitting of neon
Replies: 14
Views: 338

Re: Fabry-Perot etalon testing: Zeeman splitting of neon

Beautiful experiment!
Will you measure the Zeeman splitting to determine whether your estimate of the field strength is correct?
Cheers.
Peter
by p_zetner
Wed Feb 10, 2021 1:40 pm
Forum: Solar Radio, Magnetometry and Spectroscopy
Topic: Home-made Fabry-Perot etalon project
Replies: 5
Views: 110

Re: Home-made Fabry-Perot etalon project

Great fun!
Thanks for sharing this.
Cheers.
Peter
by p_zetner
Wed Feb 10, 2021 1:39 pm
Forum: Solar Radio, Magnetometry and Spectroscopy
Topic: Quantitative and qualitative test of etalons with an Ha tube
Replies: 17
Views: 254

Re: Quantitative and qualitative test of etalons with an Ha tube

Thanks for this informative thread!
Very enjoyable reading.
Cheers.
Peter