Search found 893 matches

by p_zetner
Mon Oct 15, 2018 7:58 pm
Forum: Solar Astronomy Shop and Swap
Topic: New Skybender tilt modules - 1.25" and 2"
Replies: 12
Views: 296

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: 259

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: 135

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: 10
Views: 200

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: 259

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: 286

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: 229

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: 141

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: 175

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: 643

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: 357

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: 357

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: 643

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: 785

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: 198

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: 374

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: 92

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: 28
Views: 605

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: 393

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: 391

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: 19
Views: 636

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: 637

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: 347

Re: September 13 in Ha

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

Cheers.
Peter