Search found 910 matches

by p_zetner
Tue Jan 01, 2019 11:03 pm
Forum: Solar Radio, Magnetometry and Spectroscopy
Topic: Geomagnetic Activity Summary for 2018
Replies: 7
Views: 185

Re: Geomagnetic Activity Summary for 2018

That’s an impressive record, Stu.
How does it compare with a solar active year?

I agree with Mark. Noisy power supplies are bad things! Often times very difficult to diagnose.

Cheers and Happy New Year.
Peter
by p_zetner
Mon Dec 24, 2018 4:48 am
Forum: SPoD Archive
Topic: Helium Disk: 08Aug2018 Spectroheliogram
Replies: 13
Views: 373

Re: Helium Disk: 08Aug2018 Spectroheliogram

Thanks for your interest and comments, everyone.

Mark, thanks for the SPOD!
by p_zetner
Sat Dec 22, 2018 4:22 pm
Forum: Solar Radio, Magnetometry and Spectroscopy
Topic: magnetic fields
Replies: 7
Views: 293

Re: magnetic fields

Here is an analysis of the Zeeman splitting in the Fe lines which I did some time ago. The spectra were taken without polarization optics. The analysis in your case would be simpler.

https://www.cloudynights.com/topic/5723 ... tic-field/
by p_zetner
Sat Dec 22, 2018 3:58 am
Forum: Solar Radio, Magnetometry and Spectroscopy
Topic: Helium Disk: 08Aug2018 Spectroheliogram
Replies: 14
Views: 602

Re: Helium Disk: 08Aug2018 Spectroheliogram

The coronal green line FeXIV 5302.86 Å is extremely weak and, previously, I would not have attempted it. It might be possible although I have not seen any professional results of imaging at this wavelength.
by p_zetner
Sat Dec 22, 2018 3:58 am
Forum: SPoD Archive
Topic: Helium Disk: 08Aug2018 Spectroheliogram
Replies: 13
Views: 373

Re: Helium Disk: 08Aug2018 Spectroheliogram

The coronal green line FeXIV 5302.86 Å is extremely weak and, previously, I would not have attempted it. It might be possible although I have not seen any professional results of imaging at this wavelength.
by p_zetner
Sat Dec 22, 2018 3:41 am
Forum: Solar Radio, Magnetometry and Spectroscopy
Topic: magnetic fields
Replies: 7
Views: 293

Re: magnetic fields

Your quarter wave plate / polarizer combination seems to be working although the Zeeman shift appears to be small. You need to generate a spectroheliogram (6302.5A) for an initial quarter wave plate / polarizer combination and one for 90 degree rotation of the polarizer. Subtract the two and you hav...
by p_zetner
Tue Dec 18, 2018 8:46 pm
Forum: Solar Radio, Magnetometry and Spectroscopy
Topic: Helium Disk: 08Aug2018 Spectroheliogram
Replies: 14
Views: 602

Re: Helium Disk: 08Aug2018 Spectroheliogram

Thanks for your comments, everyone. Stu: Maybe I overstated this a little! Zirin (Astrophysics of the Sun 1988 p198) says that "The limb-disk contrast in helium is remarkable. The strong 5876 line (called D3 because of its proximity to the D1 and D2 lines of NaI) is about 0.2 times the disk intensit...
by p_zetner
Tue Dec 18, 2018 8:46 pm
Forum: SPoD Archive
Topic: Helium Disk: 08Aug2018 Spectroheliogram
Replies: 13
Views: 373

Re: Helium Disk: 08Aug2018 Spectroheliogram

Thanks for your comments, everyone. Stu: Maybe I overstated this a little! Zirin (Astrophysics of the Sun 1988 p198) says that "The limb-disk contrast in helium is remarkable. The strong 5876 line (called D3 because of its proximity to the D1 and D2 lines of NaI) is about 0.2 times the disk intensit...
by p_zetner
Sun Dec 16, 2018 8:59 pm
Forum: SPoD Archive
Topic: Helium Disk: 08Aug2018 Spectroheliogram
Replies: 13
Views: 373

Helium Disk: 08Aug2018 Spectroheliogram

Greetings Everyone. I have been developing my processing workflow for spectroheliograms to create proper images of weak lines, especially my favourite; HeD3. Here's a result from my solitary SHG imaging session on August 8. I've included a H alpha image for comparison (taken on the same date). Aside...
by p_zetner
Sun Dec 16, 2018 8:59 pm
Forum: Solar Radio, Magnetometry and Spectroscopy
Topic: Helium Disk: 08Aug2018 Spectroheliogram
Replies: 14
Views: 602

Helium Disk: 08Aug2018 Spectroheliogram

Greetings Everyone. I have been developing my processing workflow for spectroheliograms to create proper images of weak lines, especially my favourite; HeD3. Here's a result from my solitary SHG imaging session on August 8. I've included a H alpha image for comparison (taken on the same date). Aside...
by p_zetner
Mon Nov 26, 2018 3:42 pm
Forum: This is SolarChat !!
Topic: Citizen Science
Replies: 24
Views: 1146

Re: Citizen Science

Hi Stu. Well done! I applaud what you, Mark and Alexandra are planning. There seems to be a pretty active pro-am collaboration in stellar spectroscopy and it would be exciting to see something similar happen with solar observations. It would definitely be interesting to find out if there is some nic...
by p_zetner
Wed Nov 07, 2018 6:03 pm
Forum: This is SolarChat !!
Topic: Mg II in UltraViolet
Replies: 31
Views: 1663

Re: Mg II in UltraViolet

Thanks, Bob.

I like the idea of a visit to Antarctica. Living in central Canada with some harsh winter weather, I’m pretty much set for clothing. Can’t forget to slather on the sunscreen with the enhanced UVC !

:-)
by p_zetner
Wed Nov 07, 2018 4:52 pm
Forum: This is SolarChat !!
Topic: Mg II in UltraViolet
Replies: 31
Views: 1663

Re: Mg II in UltraViolet

Well argued, Bob. If I could add to this discussion, I would address an even bigger elephant in the room: atmospheric transmission at 280nm. Here are atmospheric transmission curves at the Paranal VLT site. Paranal is located in the Atacama Desert of northern Chile on Cerro Paranal at 2,635 m altitu...
by p_zetner
Tue Oct 30, 2018 2:18 am
Forum: This is SolarChat !!
Topic: Sun in CaK Lunt B600 + Omega filter
Replies: 12
Views: 513

Re: Sun in CaK Lunt B600 + Omega filter

Very nice, Stu.
I agree with you. The Omega filter gives some contrast improvement in my system as well. Maybe it does a slightly better job than the Lunt blocking filter in suppressing neighbouring etalon modes. Looks like your filter uniformity is good.
Cheers.
Peter
by p_zetner
Tue Oct 23, 2018 8:52 pm
Forum: This is SolarChat !!
Topic: Astronomy Photographer of the Year 2018
Replies: 12
Views: 573

Re: Astronomy Photographer of the Year 2018

Congratulations, Stu!
That is a terrific image.
Cheers.
Peter
by p_zetner
Tue Oct 23, 2018 2:10 pm
Forum: This is SolarChat !!
Topic: RAW stacked image in CaK with 280mm SCT
Replies: 18
Views: 819

Re: RAW stacked image in CaK with 280mm SCT

Love the deep contrast in your processing, Valery.
My attempt to come close is below.
Are you using some kind of line or edge enhancement filter?

Cheers.
Peter
SUN_080924_AS_f800_g4_ap3973 bw_lin-enhanc_proc0.png
SUN_080924_AS_f800_g4_ap3973 bw_lin-enhanc_proc0.png (3.36 MiB) Viewed 588 times
by p_zetner
Mon Oct 22, 2018 7:44 pm
Forum: This is SolarChat !!
Topic: RAW stacked image in CaK with 280mm SCT
Replies: 18
Views: 819

Re: RAW stacked image in CaK with 280mm SCT

Hi Valery. Here's my version. Cheers. Peter SUN_080924_AS_f800_g4_ap3973 bw_proc2.png Workflow details: ImagesPlusv5.5: 2.0X scale change. Adaptive Lucy-Richardson deconvolution (200 iterations, 11x11 px) Multi-resolution sharpening. 0.5X scale change. Multi-resolution sharpening. Photoshop CS4: HDR...
by p_zetner
Mon Oct 15, 2018 7:58 pm
Forum: Solar Astronomy Shop and Swap
Topic: (SOLD OUT) New Skybender tilt modules - 1.25"
Replies: 2
Views: 866

Re: New Skybender tilt modules - 1.25" and 2"

Hi Apollo.

From what I can gather, the 1.25" Sky Bender has a female SCT thread on one side and a 1.25"OD tube on the other?
Please confirm this if you can.

Thanks.
Peter
by p_zetner
Sun Oct 14, 2018 10:49 pm
Forum: Solar Radio, Magnetometry and Spectroscopy
Topic: For Science / Math Lovers: Measurement of a Solar Filament Temperature.
Replies: 6
Views: 1084

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

Thanks Mark and Frank. I’m still kind of amazed at the kind of science results I can get from the spectroheliograph. I’ve measured solar disk rotation ( https://www.cloudynights.com/topic/574571-solar-differential-rotation-measured-with-a-spectroheliograph/?hl=%2Bdifferential+%2Brotation#entry783709...
by p_zetner
Sun Oct 14, 2018 8:50 pm
Forum: This is SolarChat !!
Topic: AR2724 & AR2725, 150mm vs 120mm, HA & WL | Oct 14th 2018
Replies: 6
Views: 309

Re: AR2724 & AR2725, 150mm vs 120mm, HA & WL | Oct 14th 2018

Marty you’re so prolific!
Another great set of images.

Cheers.
Peter
by p_zetner
Sun Oct 14, 2018 8:49 pm
Forum: This is SolarChat !!
Topic: A Sunrise in there somewhere.
Replies: 12
Views: 576

Re: A Sunrise in there somewhere.

Lovely gallery, Derek.
Some intriguing shots of strange objects and unusual landscape formations (not to mention unfamiliar activities with bathtubs). They remind me a little of Dave Bowman’s hallucinogenic space voyage at the end of 2001 A Space Odyssey.
Cheers.
Peter
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: 1084

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: 439

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

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

Cheers.
Peter