Search found 37 matches

by LTHB
Tue Sep 11, 2018 9:20 pm
Forum: This is SolarChat !!
Topic: CaK from September 4th, 2018
Replies: 2
Views: 88

CaK from September 4th, 2018

A week ago, on Sept. 4th, I could capture some CaK through a break in the clouds that lasted for a few minutes only, but the seeing was o.k. Unfortunately, after two short videos the sun was gone again before I could get a Barlow lens to get the proper focal lenght for the seeing. Processing the bet...
by LTHB
Fri Aug 31, 2018 6:44 pm
Forum: This is SolarChat !!
Topic: AR12719 High Res at 390nm, CaK and H-a in a 280mm scope.
Replies: 5
Views: 212

Re: AR12719 High Res at 390nm, CaK and H-a in a 280mm scope.

Wonderful images! It is fun and very interesting to see the same region in different wavelengths and to compare structures to see what is visible in which wavelength and how these features correlate. Thanks for showing!

Frank
by LTHB
Tue Aug 28, 2018 5:44 pm
Forum: Solar Radio, Magnetometry and Spectroscopy
Topic: 08Aug: Spectral sweep through the Ca K line
Replies: 13
Views: 469

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

Hi Peter,

very instructing and useful for judging if a CaK-filter is on band or not, thanks for posting!

Frank
by LTHB
Mon Aug 27, 2018 7:38 pm
Forum: This is SolarChat !!
Topic: CaK from August 7th with ARIES-ERF
Replies: 17
Views: 462

Re: CaK from August 7th with ARIES-ERF

Hi Valery, unfortunately I did not keep the video (some GBs) for lack of space on my hard drive! The image I posted was processed from a stack of 200 frames - if you think this is still worth reprocessing I can email you the unprocessed tif-file. Next time I get the chance to capture decent CaK I wi...
by LTHB
Mon Aug 27, 2018 7:03 pm
Forum: This is SolarChat !!
Topic: A random area at the Sun chromosphere in CaK with 280mm C11
Replies: 8
Views: 201

Re: A random area at the Sun chromosphere in CaK with 280mm C11

Fantastic, Valery! As Peter said, close to the DOT pictures, as far as I can tell!

I guess you are not really serious about the "relatively poor seeing", are you? Would you mind to tell about your way of processing?

Regards,

Frank
by LTHB
Mon Aug 27, 2018 6:55 pm
Forum: This is SolarChat !!
Topic: August 16 2018 AR12718 3 bands 280mm scope.
Replies: 21
Views: 533

Re: August 16 2018 AR12718 3 bands 280mm scope.

I hope so, too! I, for one, would very much like to see them!

Frank
by LTHB
Sun Aug 26, 2018 2:07 pm
Forum: This is SolarChat !!
Topic: August 16 2018 AR12718 3 bands 280mm scope.
Replies: 21
Views: 533

Re: August 16 2018 AR12718 3 bands 280mm scope.

Hi Valery, thanks (somewhat belatedly - I was very busy last week) for the info! I am also shooting CaK at 6ms (or a little less) exposure time, but I mostly stack around 200 frames. I've never used a stack of more than 1000 frames, but I recall that Emil Kraaikamp says somewhere on his website, tha...
by LTHB
Sun Aug 26, 2018 11:42 am
Forum: This is SolarChat !!
Topic: Eliminating bad frames during stacking?
Replies: 9
Views: 200

Re: Eliminating bad frames during stacking?

If you want to exclude a couple of bad frames from stacking in Autostakkert you can also do that by deselecting them in Autostakkert: Just click through the video (loaded in Autostakkert) frame by frame (or/and use the slider to move through the video) and hit the space-bar for each bad frame. You s...
by LTHB
Sun Aug 26, 2018 10:53 am
Forum: This is SolarChat !!
Topic: CaK from August 7th with ARIES-ERF
Replies: 17
Views: 462

Re: CaK from August 7th with ARIES-ERF

Hello Christian, thanks for the suggestion! When I apply a (rather aggressive) unsharp mask only (i.e. no deconvolution) the best I get looks like this: https://c2.staticflickr.com/2/1882/44226015162_549154f95f_o.jpg Unfortunately this does not really seem to improve the image: While the difference ...
by LTHB
Mon Aug 20, 2018 10:11 am
Forum: This is SolarChat !!
Topic: A new small group - images added
Replies: 10
Views: 199

Re: A new small group

Hi Raf,

beautiful shots!

I caught the same group in CaK in late afternoon:

Image

Image

Quite interesting to see how much has changed over a few hours!

Regards,

Frank
by LTHB
Sat Aug 18, 2018 9:27 pm
Forum: This is SolarChat !!
Topic: August 16 2018 AR12718 3 bands 280mm scope.
Replies: 21
Views: 533

Re: August 16 2018 AR12718 3 bands 280mm scope.

Hi Valery,

great pictures! The CaK in particular is terrific - I haven't seen any CaK image taken with amateur equipment that comes closer to the DOT images in terms of detail and resolution!

Would you tell us what exposure time you used and how many frames you stacked?

Regards,

Frank
by LTHB
Thu Aug 16, 2018 6:24 pm
Forum: This is SolarChat !!
Topic: CaK in high resolution of August 3rd and 6th
Replies: 8
Views: 253

Re: CaK in high resolution of August 3rd and 6th

Scope was a Mewlon 210 with Lunt CaK filter, double-stacked with a yellow PST filter, Aries front ERF.

Regards,

Frank
by LTHB
Wed Aug 15, 2018 8:02 pm
Forum: This is SolarChat !!
Topic: CaK in high resolution of August 3rd and 6th
Replies: 8
Views: 253

Re: CaK in high resolution of August 3rd and 6th

Thanks, Alexandra and Mark! Rainer, you are right, the images are quite dark, certainly a lot darker than most CaK images posted here on solarchat or on CN, and I am not sure if I find them aesthetically very pleasing. However, my intention in processing them was to get a "look" similar to the CaK i...
by LTHB
Tue Aug 14, 2018 9:20 pm
Forum: This is SolarChat !!
Topic: CaK in high resolution of August 3rd and 6th
Replies: 8
Views: 253

CaK in high resolution of August 3rd and 6th

Two more CaK images from August 3rd and August 6th, and two more attempts at image processing that takes the DOT pictures as a standard.

Image

Image

Regards,

Frank
by LTHB
Mon Aug 13, 2018 10:55 am
Forum: This is SolarChat !!
Topic: Sunset Moonset on Walters Mountain + Venting Satellite
Replies: 13
Views: 335

Re: Sunset Moonset on Walters Mountain + Venting Satellite

Wonderful pictures, Derek, thanks for sharing!

Frank
by LTHB
Sat Aug 11, 2018 7:26 pm
Forum: This is SolarChat !!
Topic: CaK from August 7th with ARIES-ERF
Replies: 17
Views: 462

Re: CaK from August 7th with ARIES-ERF

Hi all, looking for a standard for correct/appropriate processing of my CaK images I browsed the webpage of the (now mothballed) Dutch Open Telescope (DOT). I found this one: http://www.staff.science.uu.nl/~rutte101/dot/albums/images/20060923-mosaic-ca.png The DOT is, of course, much bigger than our...
by LTHB
Fri Aug 10, 2018 4:15 pm
Forum: This is SolarChat !!
Topic: CaK from August 7th with ARIES-ERF
Replies: 17
Views: 462

Re: CaK from August 7th with ARIES-ERF

Hi Valery, I just sent you a PM with the unprocessed stack of the image in my first post (a tif-file). After that I just saw your post with the reprocessed image, thanks! That's really interesting and it speaks precisely to the point of my question! I have used imppg's deconvolution tool for process...
by LTHB
Fri Aug 10, 2018 12:32 am
Forum: This is SolarChat !!
Topic: CaK from August 7th with ARIES-ERF
Replies: 17
Views: 462

Re: CaK from August 7th with ARIES-ERF

Thanks, Eric and Mark! Eric, I can see why the picture looks underprocessed to you (and to Valery, too),while in fact I did quite a lot of processing: It looks slightly blurred, but I could not improve that by much. My second version: https://c1.staticflickr.com/1/859/29017337817_5044c29643_o.jpg Re...
by LTHB
Thu Aug 09, 2018 1:31 pm
Forum: This is SolarChat !!
Topic: CaK from August 7th with ARIES-ERF
Replies: 17
Views: 462

Re: CaK from August 7th with ARIES-ERF

Thanks, Alexandra and Valery! Valery, I just try to send you a PM with the unprocessed stack from Autostakkert3, but failed, probably because the file is too large (15MB). Can I send it via email? - It would be great if I could see your processing results and learn! I also just searched a little for...
by LTHB
Wed Aug 08, 2018 2:07 pm
Forum: This is SolarChat !!
Topic: CaK from August 7th with ARIES-ERF
Replies: 17
Views: 462

CaK from August 7th with ARIES-ERF

Sun is shining even in northern Germany now AND seeing was o.k. yesterday, so another rare opportunity to get the ARIES-ERF out and capture some CaK. https://c2.staticflickr.com/2/1794/43877196782_c92657b4cf_o.jpg This is the result of two afternoons trying to understand how to use imppg, i.e. decon...
by LTHB
Sun Nov 19, 2017 2:01 pm
Forum: Solar Astronomy Shop and Swap
Topic: Wanted: Aperture Iris for solar observing
Replies: 9
Views: 683

Re: Wanted: Aperture Iris for solar observing

You can find a little more information on the Baader website: http://www.baader-planetarium.com/en/stufenlos-einstellbare-irisblende-13---113mm.html?___from_store=de# There you see that the iris diaphragm is obviously designed for use with the Baader filter cells. The caption there says that the fil...
by LTHB
Thu Sep 21, 2017 8:52 am
Forum: Solar Scope Modifications
Topic: Removing barlow from Quark
Replies: 17
Views: 2213

Re: Removing barlow from Quark

Sorry, I misunderstood your question! Yes, you have to remove one screw before you can separate the red etalon body from the main black ring (the two parts on the lower left and in the center of the second of the three pictures in my post above). This screw is on the side of the red part, I removed ...
by LTHB
Tue Sep 19, 2017 8:32 pm
Forum: This is SolarChat !!
Topic: First CaK images with ARIES-ERF
Replies: 9
Views: 647

Re: First CaK images with ARIES-ERF

Hi Valery, 1) The Mewlon has an F/D of 11.5, so with the 2xPowermate it should be 23. (As far as I know the Powermate's magnification factor is almost independent of its distance to the sensor.) For the first picture above the exposure was 3.8ms, gain was 253, for the second and third 20ms exposure ...
by LTHB
Tue Sep 19, 2017 7:51 pm
Forum: Solar Scope Modifications
Topic: Removing barlow from Quark
Replies: 17
Views: 2213

Re: Removing barlow from Quark

I'm not quite sure what you mean: two of the four screws (upper left and lower right) on the left hand side of the second picture in my last post? If yes: I didn't remove these screws/the black ring so far, so I cannot really tell if they can be removed without damaging the filter. However, for unfa...
by LTHB
Mon Sep 18, 2017 5:33 pm
Forum: This is SolarChat !!
Topic: First CaK images with ARIES-ERF
Replies: 9
Views: 647

Re: First CaK images with ARIES-ERF

Hi Derek and Valery, thanks! The telescope is a Mewlon 210 with a Lunt B1800 straight-through filter, double-stacked with a filter taken from a PST, the camera an ASI174. I started with CaK because in the Mewlon setup the Powermate is the only piece of glass between the sun and the sensor (except fo...