Search found 899 matches

by p_zetner
Wed Nov 07, 2018 6:03 pm
Forum: This is SolarChat !!
Topic: Mg II in UltraViolet
Replies: 43
Views: 1150

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: 43
Views: 1150

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: 13
Views: 331

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: 406

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: 21
Views: 570

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 339 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: 21
Views: 570

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: 14
Views: 719

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: 916

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: 213

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: 13
Views: 404

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: 916

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: 323

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: 285

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: 231

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: 250

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: 25
Views: 779

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: 5
Views: 1129

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: 5
Views: 1129

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: 25
Views: 779

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: 906

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: 281

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: 458

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: 157

Re: AR2723 September 30th

What a beautiful little dipole!

Well done, Franco. Nice image.

Cheers.
Peter