Search found 450 matches

by christian viladrich
Wed Jan 23, 2019 9:27 pm
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: What camera?
Replies: 12
Views: 126

Re: What camera?

Hello Alexandra, The first question is what is your Ha filter ? Indeed, the Ha solar filter sets the F/D, which in turn sets the size of the pixel, which in turn sets the sensor. If your Ha filter need F/30 or more, the short answer is the IMX174. Smaller pixel sizes won't make the job. In a nutshel...
by christian viladrich
Wed Jan 23, 2019 9:14 pm
Forum: This is SolarChat !!
Topic: What does 656.281 nm look like?
Replies: 9
Views: 79

Re: What does 656.281 nm look like?

BTW, the Televue X2.5 is not telecentric. It is much better to use a telecentric system.
by christian viladrich
Wed Jan 23, 2019 9:12 pm
Forum: This is SolarChat !!
Topic: What does 656.281 nm look like?
Replies: 9
Views: 79

Re: What does 656.281 nm look like?

Hello phil, There are 3 criteria which may help to find the center of the band : - measure the average intensity of the image => the darkest image is the one on the center of the band ; - the short dark "little things" coming in bunches are groups of spicules seen from above. They are at the border ...
by christian viladrich
Sun Jan 06, 2019 11:10 am
Forum: This is SolarChat !!
Topic: Ca K and G band images take on July 1 and 8, 2018
Replies: 12
Views: 270

Re: Ca K and G band images take on July 1 and 8, 2018

Thanks Pedro :-) Mark, regarding the ASI290, the S/N max is 6.9 bits while it is 7.5 bits for the IMX174. So, in situations where there is a lot of light (e.g. use of an Hershel wedge), the IMX 174 will give better results. In Ca K, light could me missing. I had some good results with the ASI290 on ...
by christian viladrich
Sun Jan 06, 2019 10:51 am
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: Multiple aperture off axis mask with white light film on dob
Replies: 6
Views: 208

Re: Multiple aperture off axis mask with white light film on dob

As explained by Mark, this is a bad idea. Make it simple and go for only one aperture. Here is a simulations comparing the effect on the figure of diffraction of full aperture, two and four holes : http://astrosurf.com/viladrich/astro/instrument/sensitivity/planche-obstruction.jpg http://astrosurf.c...
by christian viladrich
Sat Jan 05, 2019 5:23 pm
Forum: This is SolarChat !!
Topic: Ca K and G band images take on July 1 and 8, 2018
Replies: 12
Views: 270

Re: Ca K and G band images take on July 1 and 8, 2018

Hello Mark,
The focal length is close to 3000 mm.
by christian viladrich
Sat Jan 05, 2019 5:23 pm
Forum: SPoD Archive
Topic: Ca K and G band images take on July 1 and 8, 2018
Replies: 8
Views: 192

Re: Ca K and G band images take on July 1 and 8, 2018

Hello Mark,
The focal length is close to 3000 mm.
by christian viladrich
Fri Jan 04, 2019 8:42 pm
Forum: This is SolarChat !!
Topic: Ca K and G band images take on July 1 and 8, 2018
Replies: 12
Views: 270

Ca K and G band images take on July 1 and 8, 2018

Dear All, I still have some images taken on 2018 waiting for processing. Here are some of them. The solar activity was not much higher than now :-( The seeing was quite good on July 1, 2018 : http://astrosurf.com/viladrich/astro/soleil/2018/CaK-1July2018-9h34mnUT-TOA150-IDS3370.jpg Here are close-up...
by christian viladrich
Fri Jan 04, 2019 8:42 pm
Forum: SPoD Archive
Topic: Ca K and G band images take on July 1 and 8, 2018
Replies: 8
Views: 192

Ca K and G band images take on July 1 and 8, 2018

Dear All, I still have some images taken on 2018 waiting for processing. Here are some of them. The solar activity was not much higher than now :-( The seeing was quite good on July 1, 2018 : http://astrosurf.com/viladrich/astro/soleil/2018/CaK-1July2018-9h34mnUT-TOA150-IDS3370.jpg Here are close-up...
by christian viladrich
Fri Nov 23, 2018 1:25 pm
Forum: This is SolarChat !!
Topic: Hawk Repurposed My Solar Scope
Replies: 9
Views: 414

Re: Hawk Repurposed My Solar Scope

Beautiful !
by christian viladrich
Fri Nov 23, 2018 8:09 am
Forum: This is SolarChat !!
Topic: Citizen Science
Replies: 24
Views: 1146

Re: Citizen Science

This is a great idea ! Here are the links to some images. Newton 300 mm, G band, K-line, filigrees, faculae http://astrosurf.com/viladrich/astro/soleil/wl/2018/AR2720-25August2018-9h25min-N300-B1920-430nm.jpg http://astrosurf.com/viladrich/astro/soleil/wl/2018/AR2719-24August2018-11h43mnUT-N300-396n...
by christian viladrich
Mon Nov 12, 2018 7:21 pm
Forum: This is SolarChat !!
Topic: I told ya so... Comets causing sunspots.
Replies: 2
Views: 346

Re: I told ya so... Comets causing sunspots.

I am afraid sunspots are the effect of localized strong magnetic fields in the photosphere (and in the layer below).
They have nothing to do with comets.
by christian viladrich
Sun Nov 11, 2018 8:31 pm
Forum: This is SolarChat !!
Topic: Mg II in UltraViolet
Replies: 31
Views: 1661

Re: Mg II in UltraViolet

Interesting info Raf :-)
I didn't know they have these small size Cassegrain scopes.They have quartz mirrors which is very nice. I have no idea of the optical quality.
by christian viladrich
Sun Nov 11, 2018 7:16 pm
Forum: This is SolarChat !!
Topic: Mg II in UltraViolet
Replies: 31
Views: 1661

Re: Mg II in UltraViolet

Hello Bob, Here are the simulations for a re-spaced classic C8 : http://astrosurf.com/viladrich/astro/instrument/sensitivity/sensitivity-analysis-SC8-Plate.htm The diffraction limited flat-field increases by a factor of four when the Schmidt plate position is set 230mm ahead its nominal position. ht...
by christian viladrich
Fri Nov 09, 2018 7:46 pm
Forum: This is SolarChat !!
Topic: Mg II in UltraViolet
Replies: 31
Views: 1661

Re: Mg II in UltraViolet

Hi Bob,
Is this the C8 or the C8 EdgeHD ?
by christian viladrich
Thu Nov 08, 2018 8:08 pm
Forum: This is SolarChat !!
Topic: Mg II in UltraViolet
Replies: 31
Views: 1661

Re: Mg II in UltraViolet

Hi Bob,
I have done some simulations there for a re-spaced C14 :
http://astrosurf.com/viladrich/astro/in ... -Plate.htm
I can run some more for the C8 if it is helpfull.
Christian
by christian viladrich
Wed Nov 07, 2018 8:49 pm
Forum: This is SolarChat !!
Topic: Astronomie solaire
Replies: 11
Views: 644

Re: Astronomie solaire

Hi,
We will keep you informed when the English version is ready.
by christian viladrich
Mon Nov 05, 2018 7:40 pm
Forum: This is SolarChat !!
Topic: Astronomie solaire
Replies: 11
Views: 644

Re: Astronomie solaire

Thanks Ralf and Pedro for your kind comments :-)

This give us even more motivation to get the English version ready ASAP.

Best regards
Christian
by christian viladrich
Tue Oct 30, 2018 7:22 pm
Forum: Solar Scope Modifications
Topic: My New BinChannel ERF
Replies: 13
Views: 613

Re: My New BinChannel ERF

40 nm FWHM in both Ca K and Ha is amazing. What far goes the blockage in IR ? 1000 nm ? 1200 nm ?

Any idea of the optical quality (P-V or rms wavefront) ?
by christian viladrich
Mon Oct 29, 2018 9:28 pm
Forum: Solar Scope Modifications
Topic: My New BinChannel ERF
Replies: 13
Views: 613

Re: My New BinChannel ERF

Looks good !
Any idea of the optical quality ? Any transmission curve available ?
by christian viladrich
Sun Oct 28, 2018 9:18 pm
Forum: This is SolarChat !!
Topic: Sun Exhibition - London Science Museum
Replies: 8
Views: 349

Re: Sun Exhibition - London Science Museum

Very interesting :-)
I am planning a visit there in January.
Christian
by christian viladrich
Wed Oct 24, 2018 9:12 pm
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: BF30 ITF replacement
Replies: 10
Views: 935

Re: BF30 ITF replacement

Hello Bob,
Thanks for the valuable information.
What is the orginal source of information for these figures :
download/file.php?id=34786
Thanks !
by christian viladrich
Mon Oct 22, 2018 7:31 am
Forum: This is SolarChat !!
Topic: Very Long ferret! 10-21-2018
Replies: 5
Views: 418

Re: Very Long ferret! 10-21-2018

Hello Apollo
Could you give data / hour of observation ?
Best regards
Christian