Search found 337 matches

by krakatoa1883
Sun Nov 18, 2018 12:31 pm
Forum: This is SolarChat !!
Topic: Today's SUN (20181116) with good seeing
Replies: 12
Views: 175

Re: Today's SUN (20181116) with good seeing

Excellent images, Pedro, thanks for detailing the flat field procedure, very useful.
by krakatoa1883
Sun Nov 18, 2018 12:27 pm
Forum: This is SolarChat !!
Topic: Still orbiting around the Sun....
Replies: 6
Views: 115

Re: Still orbiting around the Sun....

Thanks to all for your comments, very kind :)

The group is still there, both the trailing and following spots are slightly larger than yesterday, look at it if you can.
by krakatoa1883
Sat Nov 17, 2018 3:12 pm
Forum: This is SolarChat !!
Topic: Still orbiting around the Sun....
Replies: 6
Views: 115

Still orbiting around the Sun....

Today first clear and sunny day since October 20th. Of course the seeing is terrible as the atmospheric circulation changed from a humid and cloudy African anticyclone to a dry Russian cyclone together with an abrupt temperature fall. No high resolution possible however I did my best to capture a fu...
by krakatoa1883
Thu Nov 15, 2018 2:01 pm
Forum: This is SolarChat !!
Topic: Sunspot 2726, Big Prom, Full Disc | 150mm & 40mm HA | Nov 13th 2018
Replies: 14
Views: 252

Re: Sunspot 2726, Big Prom, Full Disc | 150mm & 40mm HA | Nov 13th 2018

You should determine by yourself what is the reducing factor for a given distance from the converging lens to the camera sensor. It's enough to point the scope to a distant object and see how larger becomes the field of view with the reducer. There are actually different reducers available for use w...
by krakatoa1883
Wed Nov 14, 2018 11:45 am
Forum: This is SolarChat !!
Topic: Sunspot 2726, Big Prom, Full Disc | 150mm & 40mm HA | Nov 13th 2018
Replies: 14
Views: 252

Re: Sunspot 2726, Big Prom, Full Disc | 150mm & 40mm HA | Nov 13th 2018

Excellent work, Marty. Why don't you insert a focal reducer before the camera ? It would help to obtain a larger view.
by krakatoa1883
Wed Nov 14, 2018 11:43 am
Forum: This is SolarChat !!
Topic: Cool calcium prom 11-13-2018
Replies: 9
Views: 163

Re: Cool calcium prom 11-13-2018

Fine prom video, Apollo.
by krakatoa1883
Mon Nov 12, 2018 1:29 pm
Forum: This is SolarChat !!
Topic: Sol from the 10th of November 2018.
Replies: 11
Views: 166

Re: Sol from the 10th of November 2018.

Fantastic proms, Eric!
by krakatoa1883
Mon Nov 12, 2018 1:27 pm
Forum: This is SolarChat !!
Topic: Solar panorama in Ca II K 11th Nov.
Replies: 8
Views: 174

Re: Solar panorama in Ca II K 11th Nov.

You CaK setup is a winner, Stu, nice image!
by krakatoa1883
Mon Nov 12, 2018 1:25 pm
Forum: This is SolarChat !!
Topic: Sun November 11th
Replies: 16
Views: 249

Re: Sun November 11th

At least you're able to see the Sun, my last image was one month ago, since then always cloudy here :lol:

Nice disc, and how many colors around you, a very beautiful nature
by krakatoa1883
Sun Nov 11, 2018 8:04 pm
Forum: This is SolarChat !!
Topic: Mg II in UltraViolet
Replies: 43
Views: 1134

Re: Mg II in UltraViolet

In my opinion for hires imaging in the near UV correcting the system for SA is much more important that enlarging the D-L field, thus an all-reflecting system would definitely be much more preferable than modifying a SCT. BTW, one can consider a commercial Cassegrain , it is a relatively inexpensive...
by krakatoa1883
Sun Nov 11, 2018 7:47 pm
Forum: This is SolarChat !!
Topic: Ha Full Disk 11th November
Replies: 13
Views: 209

Re: Ha Full Disk 11th November

Nice disc, Mark, with lot of details for a solar minimum. The bright zone on the left of the center disc has now evolved in a B-class sunspot group. It is bright in UV and SE of it another bright patch is developing.
by krakatoa1883
Sun Nov 11, 2018 2:33 pm
Forum: This is SolarChat !!
Topic: High latitude sunspot
Replies: 17
Views: 437

Re: High latitude sunspot

Thanks, Mark, graph is very clear. I put my Wolf numbers in a graph too, the overall (N + S) double peak is apparent
Wolf.jpg
Wolf.jpg (23.56 KiB) Viewed 264 times
by krakatoa1883
Fri Nov 09, 2018 4:18 pm
Forum: This is SolarChat !!
Topic: High latitude sunspot
Replies: 17
Views: 437

Re: High latitude sunspot

I remember that spot, it was actually at even higher latitude (+36°) however as it appeared already close to the W limb the magnetic pattern was unclear, may be the N pole is preceding but I am not sure
0408L.jpg
0408L.jpg (32.14 KiB) Viewed 343 times
Thanks Alexandra for the comparison box.
by krakatoa1883
Thu Nov 08, 2018 8:02 pm
Forum: This is SolarChat !!
Topic: High latitude sunspot
Replies: 17
Views: 437

High latitude sunspot

It's raining here (since three weeks...) :( but browsing SDO images a high latitude spot is present, maybe belonging to the 25th cycle. Has anyone already imaged it ?
by krakatoa1883
Mon Nov 05, 2018 11:46 am
Forum: This is SolarChat !!
Topic: Sun today 110418
Replies: 16
Views: 337

Re: Sun today 110418

Good images, Franco, lovely processing.
by krakatoa1883
Mon Nov 05, 2018 11:46 am
Forum: SPoD Archive
Topic: Sun today 110418
Replies: 11
Views: 197

Re: Sun today 110418

Good images, Franco, lovely processing.
by krakatoa1883
Thu Nov 01, 2018 8:23 pm
Forum: This is SolarChat !!
Topic: Astronomie solaire
Replies: 12
Views: 417

Astronomie solaire

I just received this book already reported by Christian in the shop section of the forum: http://www.astronomiesolaire.com/index.php Wonderful is all I can say, I am sure it will soon become the bible of the advanced solar imager. It reminds me of another great book, High Resolution Astrophotography...
by krakatoa1883
Wed Oct 31, 2018 9:59 am
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: Experimenting calcium imaging with small refractors
Replies: 33
Views: 1382

Re: Experimenting calcium imaging with small refractors

The color of the coating corresponds to the color or combination of colors that is most reflected out. The CIE chromaticity diagram may help in understanding what colors pass least through a given lens. If one knows the index of refraction of the coating the %T (or the % reflectance) can be easily c...
by krakatoa1883
Tue Oct 30, 2018 9:30 am
Forum: This is SolarChat !!
Topic: 20181030 CaH Prominences
Replies: 4
Views: 175

Re: 20181030 CaH Prominences

Nice image, Thomas!
by krakatoa1883
Mon Oct 29, 2018 12:15 pm
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: Experimenting calcium imaging with small refractors
Replies: 33
Views: 1382

Re: Experimenting calcium imaging with small refractors

wow... really, those images show much contrast as if they were taken through a DS filter. The scope shall be certainly good but it seems that most of the result has to be attributed to the specific K module used.
by krakatoa1883
Sun Oct 28, 2018 7:56 pm
Forum: This is SolarChat !!
Topic: Sol from the 25th of October 2018.
Replies: 7
Views: 154

Re: Sol from the 25th of October 2018.

Nice discs, Eric, how much contrast in your proms ! well done!
by krakatoa1883
Sun Oct 28, 2018 7:54 pm
Forum: This is SolarChat !!
Topic: Solar minimum 28th October
Replies: 11
Views: 235

Re: Solar minimum 28th October

Beautiful discs, Alexandra, I set this image as my desktop background :D
by krakatoa1883
Sun Oct 28, 2018 2:01 pm
Forum: This is SolarChat !!
Topic: Sun in CaK Lunt B600 + Omega filter
Replies: 13
Views: 329

Re: Sun in CaK Lunt B600 + Omega filter

Really fine images, Stu. Have you noted any difference compared with B600 alone ?
by krakatoa1883
Thu Oct 25, 2018 8:41 am
Forum: This is SolarChat !!
Topic: Spectacular eruption captured on AIA image
Replies: 10
Views: 271

Re: Spectacular eruption captured on AIA image

Fantastic, thanks for sharing!