Search found 2150 matches

by christian viladrich
Thu Nov 30, 2023 7:13 pm
Forum: Solar Scope Modifications
Topic: LS50 at he BACK of a scope?
Replies: 27
Views: 2316

Re: LS50 at he BACK of a scope?

I really don't understand. I've been reading for years that a collimated beam only has the main beam perpendicular, whereas a telecentric system has the entire beam perpendicular. It's written by Baader, TV and now you tell me that everything is different. I'm going to shoot myself and drown. :cry:...
by christian viladrich
Wed Nov 29, 2023 7:12 pm
Forum: Solar Astronomy Shop and Swap
Topic: Unique opportunity to purchase an observatory class Barr Associates Ca K filter
Replies: 1
Views: 813

Unique opportunity to purchase an observatory class Barr Associates Ca K filter

I’m selling my Ca K Barr Associates filter. This is a two-cavity 2.6 A FWHM filter. DayStar or Lunt Ca K filters are only one cavity (meaning less blocking of photospheric light). Measurements of the filter are presented here : http://astrosurf.com/viladrich/astro/instrument/spectro/CaK/Barr/CaK-Bar...
by christian viladrich
Wed Nov 29, 2023 5:18 pm
Forum: Solar Scope Modifications
Topic: LS50 at he BACK of a scope?
Replies: 27
Views: 2316

Re: LS50 at he BACK of a scope?

Please explain me this problem. If we talk about the effect of F on FWHM, then it is quite clear that as F increases, FWHM decreases because the beam angle is closer to perpendicular, which is the ideal condition. What I don't understand is the connection between F and the telecentric beam. relativ...
by christian viladrich
Tue Nov 28, 2023 12:38 pm
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: Player One Poseidon-C Pro + Nikon 180ED F/2.8
Replies: 2
Views: 348

Re: Player One Poseidon-C Pro + Nikon 180ED F/2.8

Hi Pedro,
What kind of adapter you used to go from the Nikon mount to the camera mount ?
Thanks !
by christian viladrich
Tue Nov 28, 2023 11:26 am
Forum: Solar Scope Modifications
Topic: Blackest black paint?
Replies: 11
Views: 3212

Re: Blackest black paint?

Thanks for the information guys !

I use flocking or paint depending of the situation (size of the reflecting surface).
by christian viladrich
Tue Nov 28, 2023 11:23 am
Forum: Solar Scope Modifications
Topic: LS50 at he BACK of a scope?
Replies: 27
Views: 2316

Re: LS50 at he BACK of a scope?

Hi there, The mica graph is a bit oldish. You can have a look at the upadated graphs for mica-spaced and air-space etalons here (near page bottom) : http://astrosurf.com/viladrich/astro/instrument/solar/FP-Coro.htm Full data for mica-space etalons (text file) : http://astrosurf.com/viladrich/astro/i...
by christian viladrich
Tue Nov 21, 2023 5:38 pm
Forum: This is SolarChat !!
Topic: 18 August belated solar images taken with the 300 mm solar Newtonian and various filters from violet to near-UV
Replies: 20
Views: 1226

Re: 18 August belated solar images taken with the 300 mm solar Newtonian and various filters from violet to near-UV

Thanks to all !! Very good collection, thanks for sharing. There is a nice 3d effect of some granules in the wl images. Indeed Dennis, this 3D effet is quite nice. It is larger when observing near the limb. Great images and an interesting comparison. I've never tried solar Ca imaging, only Ha. The d...
by christian viladrich
Mon Nov 20, 2023 11:11 am
Forum: This is SolarChat !!
Topic: Some multiband image from June
Replies: 17
Views: 897

Re: Some multiband image from June

Nice ste of images Sergio !
The FLT132 is doing good in near-UV, and the Mak is great for Ha.
by christian viladrich
Mon Nov 20, 2023 11:05 am
Forum: This is SolarChat !!
Topic: ISS transit Full Disk
Replies: 11
Views: 630

Re: ISS transit Full Disk

Very nice. Well done !
by christian viladrich
Mon Nov 20, 2023 11:03 am
Forum: This is SolarChat !!
Topic: 18 August belated solar images taken with the 300 mm solar Newtonian and various filters from violet to near-UV
Replies: 20
Views: 1226

18 August belated solar images taken with the 300 mm solar Newtonian and various filters from violet to near-UV

Hi, Here is a set of images taken on August 18 with a 300 mm solar Newtonian and filters from the violet to the near-UV. The seeing conditions were rather good and stable. First, an image taken with the Altair G band filter. Note the numerous intergranular bright points, and in the spot on the right...
by christian viladrich
Sat Nov 18, 2023 12:11 pm
Forum: This is SolarChat !!
Topic: Prominence with 3nm Ha filter?
Replies: 14
Views: 763

Re: Prominence with 3nm Ha filter?

Well done Minh !

It is quite interesting that the Astrodon 3 nm shows prom while Antlia 3 nm don't.
by christian viladrich
Fri Nov 17, 2023 6:40 pm
Forum: This is SolarChat !!
Topic: Triple stack with a singe filter - just being silly...
Replies: 9
Views: 476

Re: Triple stack with a singe filter - just being silly...

I'm haunted by another stupidity in my head. On the 150mm refractor, put four tiltable LS40s in front. This would solve the DERF and DSII etalon. The surface would be the same as the LS80, but the angular resolution could be better. The question is what the diffractions from the four etalons would ...
by christian viladrich
Wed Nov 15, 2023 8:37 pm
Forum: This is SolarChat !!
Topic: Using a focal reducer with a C9.25 and DSLR to image eclipses?
Replies: 20
Views: 1070

Re: Using a focal reducer with a C9.25 and DSLR to image eclipses?

Hi, Are you using the C9.25 Edge HD or the "classic" C9.25 ? What kind of focal reducer are you planing to use ? The usual f6.3 reducer is of rather bad optical quality. The reducer of the C9.25 EgeHD est excellent, but very expensive. What about using a telescope with about 1000 m focal l...
by christian viladrich
Wed Nov 08, 2023 7:48 pm
Forum: Annular Solar Eclipse October 14 2023
Topic: Lunar Limb Profile from C2 Bailey's Beads Progression
Replies: 4
Views: 316

Re: Lunar Limb Profile from C2 Bailey's Beads Progression

Splendid !

This is an excellent idea to reduce progressively the solar diameter.
by christian viladrich
Sun Nov 05, 2023 6:54 pm
Forum: Annular Solar Eclipse October 14 2023
Topic: October annular eclipse from Forest Gump Hill, Utah, USA
Replies: 5
Views: 312

Re: October annular eclipse from Forest Gump Hill, Utah, USA

christian viladrich wrote: ↑Thu Nov 02, 2023 7:46 pm Kevin, it is probably worth experimenting a bit about the lunar limb "reconstruction". The images I used for this were 1s apart, but I'll try with images taken 0.5 s apart. Maybe some change of coordinates is worth trying too (rectangul...
by christian viladrich
Thu Nov 02, 2023 7:49 pm
Forum: Annular Solar Eclipse October 14 2023
Topic: annular solar eclipse 14/10/23
Replies: 8
Views: 1426

Re: annular solar eclipse 14/10/23

Splendid !

The use of the 393-3 nm is an excellent idea !
by christian viladrich
Thu Nov 02, 2023 7:47 pm
Forum: Annular Solar Eclipse October 14 2023
Topic: Annularity in H-a from Kerrville, TX
Replies: 2
Views: 191

Re: Annularity in H-a from Kerrville, TX

Great shots Damien. Well done !
by christian viladrich
Thu Nov 02, 2023 7:46 pm
Forum: Annular Solar Eclipse October 14 2023
Topic: October annular eclipse from Forest Gump Hill, Utah, USA
Replies: 5
Views: 312

Re: October annular eclipse from Forest Gump Hill, Utah, USA

Thanks Alexandra and Kevin ! The landscape from Forest Gump Hill was beautiful. We could see Monument Valley to the South (I'll post a picture latter on). We had a very interesting atmospheric phenomenum just before sunrise. A layer of strong turbulence was visible at the naked eye just over the hor...
by christian viladrich
Wed Nov 01, 2023 8:42 pm
Forum: Annular Solar Eclipse October 14 2023
Topic: October annular eclipse from Forest Gump Hill, Utah, USA
Replies: 5
Views: 312

October annular eclipse from Forest Gump Hill, Utah, USA

Hi, Here are some images of the October 13 annular eclipse taken from Forest Gump Hill (not far away from Monument Valley) in Utah. The weather was splendid: coronal sky, no wind, very little turbulence. Too bad the eclipse was only annular... http://astrosurf.com/viladrich/astro/eclsol/2023-USA/202...
by christian viladrich
Sun Oct 08, 2023 5:38 pm
Forum: Solar Scope Modifications
Topic: Solar newton T400, version 2023
Replies: 19
Views: 2657

Re: Solar newton T400, version 2023

Petr, 2 s is way too long. Moment of good seeing are much shorter. The depth of focus depends on the square of the f-ratio. If you stop down the aperture, you increase the depth of focus, meaning your focus is not accurate enough at full aperture. This is theory, but this is also confirmed by practi...
by christian viladrich
Sun Oct 08, 2023 1:03 pm
Forum: Solar Scope Modifications
Topic: Solar newton T400, version 2023
Replies: 19
Views: 2657

Re: Solar newton T400, version 2023

Consideration should also be given to whether it is necessary for sunlight to enter the system in full at all times. For searching and focusing, it is sufficient to open the small off-axis aperture and the full aperture only for the shooting time, then close with the cover. If the ratio is 1:10, th...
by christian viladrich
Thu Oct 05, 2023 3:39 pm
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: C2 Swan-Band filter for photosphere imaging test.
Replies: 6
Views: 1647

Re: C2 Swan-Band filter for photosphere imaging test.

Indeed the C2 swan is a bit like the OIII : 511 nm instead of 500 nm. The difference is the bandpass 15 nm versus 12 nm for the Astronomik OIII. This makes exposure time a bit shorter, which can be usefull when using Astrosolar OIII. This is certainly a good idea to include this filter in the tool b...
by christian viladrich
Thu Oct 05, 2023 11:57 am
Forum: This is SolarChat !!
Topic: M1.9 flare and eruption at AR3452 10/2/2023
Replies: 32
Views: 3147

Re: M1.9 flare and eruption at AR3452 10/2/2023

This is great Warren !
The filament turns in emission (bright) at some places. Temperature must have been huge !
Well done.
by christian viladrich
Thu Oct 05, 2023 11:55 am
Forum: Solar Scope Modifications
Topic: Solar newton T400, version 2023
Replies: 19
Views: 2657

Re: Solar newton T400, version 2023

Its not hard to use a copper cylinder, grit and a drill press with the secondary mounted at 45Deg in plaster of paris to cut out the ellipse? Cheers. Andrew. Hi Andrew, Still you would need three screws for collimation and an additional one for adjusting the position of the secondary mirror. How ca...
by christian viladrich
Thu Oct 05, 2023 11:52 am
Forum: Solar Scope Modifications
Topic: Question about H-alpha double stacking
Replies: 37
Views: 3821

Re: Question about H-alpha double stacking

BTW, as an additional information : - the effective FWHM of a 1.1 A one-cavity filter with effective index of 1.6 would be 1.15 A in a telecentric beam at f/30, - the effective FWHM of a 0.6 A air-spaced etalon (such as Lunt) would be 1.08 A in a telecentric beam at f/30, So about the same. The outc...
by christian viladrich
Thu Oct 05, 2023 11:11 am
Forum: Solar Scope Modifications
Topic: Question about H-alpha double stacking
Replies: 37
Views: 3821

Re: Question about H-alpha double stacking

Hi Dennis, It does not matter whether the filter is an etalon or a dielectic (hardcoated or softcoated) filters. Years ago, I did a test with a 0.9 A etalon : http://astrosurf.com/viladrich/astro/instrument/solar/FP-contrast-2b.htm And a 1.5 A dielectric filter (Barr Associates) : http://astrosurf.c...
by christian viladrich
Wed Oct 04, 2023 8:19 pm
Forum: This is SolarChat !!
Topic: Tuning Quark a little differently.
Replies: 19
Views: 2228

Re: Tuning Quark a little differently.

Very interesting approach. A combination of tuning by compression and temperature (expansion). Very nice idea.
Thanks for sharing !
by christian viladrich
Wed Oct 04, 2023 5:33 pm
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: Commercial filter tilters
Replies: 24
Views: 3610

Re: Commercial filter tilters

Good question Denis ;-)

I've made two units with a 3D printer. They do the job, but an aluminium version would be better. I plan to contact Rafcamera to suggest he makes them.
by christian viladrich
Sat Sep 30, 2023 2:47 pm
Forum: Solar Scope Modifications
Topic: Solar newton T400, version 2023
Replies: 19
Views: 2657

Re: Solar newton T400, version 2023

This is hot stuff :D
by christian viladrich
Wed Sep 27, 2023 8:51 am
Forum: This is SolarChat !!
Topic: First attempt with a Ca K 1 A filter and a 300 mm Newtonian
Replies: 25
Views: 2397

Re: First attempt with a Ca K 1 A filter and a 300 mm Newtonian

Christian, you used the Baader FFC with the narrow filters, im wondering if a telecentric would give a even tighter bandpass. Or is the FFC "telecentric"? Denis, with the TOA 150, I use Airylab telecentric 2.7x. Compared to the FFC, I have much less ghost images and reflections with the t...
by christian viladrich
Tue Sep 26, 2023 5:55 pm
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: Measurement of a DayStar PE 0.6 A
Replies: 23
Views: 3117

Re: Measurement of a DayStar PE 0.6 A

DayStar's warranty states you can't expect their filters to perform similarly to other filters, and will not accept observational comparisons to other filter systems as proof of being out of specification. Supposedly if you have a spectroscopic scan they would accept that as verification of out-of-...
by christian viladrich
Tue Sep 26, 2023 4:37 pm
Forum: SPoD Archive
Topic: Travel to US for Annular Eclipse 2023
Replies: 16
Views: 1758

Re: Travel to US for Annular Eclipse 2023

Michaels,

George just told me Monument Valley Monument is closed for the eclipse :
https://www.deseret.com/utah/2023/9/18/ ... ley-closed

Still, this is road 42, road 163 seems to remain open.

Christian
by christian viladrich
Tue Sep 26, 2023 4:37 pm
Forum: Annular Solar Eclipse October 14 2023
Topic: Travel to US for Annular Eclipse 2023
Replies: 18
Views: 3393

Re: Travel to US for Annular Eclipse 2023

Michaels,

George just told me Monument Valley Monument is closed for the eclipse :
https://www.deseret.com/utah/2023/9/18/ ... ley-closed

Still, this is road 42, road 163 seems to remain open.

Christian
by christian viladrich
Sat Sep 23, 2023 7:07 pm
Forum: This is SolarChat !!
Topic: White Light or H Alpha for eclipse viewing?
Replies: 7
Views: 450

Re: White Light or H Alpha for eclipse viewing?

I plan on doing very simple white light imaging with a 150-600 zoom and a 1.4x extender.
Ca K imaging would be an option. Still, it would meant having more stuff to take by plane.
by christian viladrich
Sat Sep 23, 2023 5:39 pm
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: If CaK is best at F10 -
Replies: 59
Views: 5616

Re: If CaK is best at F10 -

Great inputs Bob !
by christian viladrich
Sat Sep 23, 2023 3:39 pm
Forum: This is SolarChat !!
Topic: Maksutoc-Cassegrain Suitability
Replies: 17
Views: 1036

Re: Maksutoc-Cassegrain Suitability

Hi Brian, About your 150 mm refractor, you can also use a subaperture 50 mm red filter for Ha, and a subaperture 50 mm blue filter for Ca K. All my Ca K images are done with a 50 mm subaperture blue filter. It is just OK. The only issue is to be able to install the subaperture filter far enough from...
by christian viladrich
Sat Sep 23, 2023 1:03 pm
Forum: This is SolarChat !!
Topic: First attempt with a Ca K 1 A filter and a 300 mm Newtonian
Replies: 25
Views: 2397

Re: First attempt with a Ca K 1 A filter and a 300 mm Newtonian

but also frustrating because it is very noisy due to the very weak signal, and a [bad-word] reflection that I have never been able to eliminate it completely. I had completely the same with my 1a Alluxa, try reversing the filter, I found it went when I did this. Excellent idea ! Both faces look sim...
by christian viladrich
Sat Sep 23, 2023 12:41 pm
Forum: This is SolarChat !!
Topic: Maksutoc-Cassegrain Suitability
Replies: 17
Views: 1036

Re: Maksutoc-Cassegrain Suitability

Thanks all for the comments. Christian,if I go ahead I'm limited to using a folded optical system to be manageable on the mount and fit in the dome. The mak I have an eye on (very preliminàry) is the 7" SkyWatcher OTA. It is just a potential option vs the SCTs https://skywatcher.com/product/bk...
by christian viladrich
Sat Sep 23, 2023 12:20 pm
Forum: This is SolarChat !!
Topic: Maksutoc-Cassegrain Suitability
Replies: 17
Views: 1036

Re: Maksutoc-Cassegrain Suitability

Does the Astrosolar 3.8 film not work with the g-band filter? Could be a cheap workaround. In good conditions, you could use a 10 nm G-band filter with the Astrosolar 3.8. Here is an example with the Andover 430-10 nm) : http://astrosurf.com/viladrich/astro/soleil/wl/2023/2023-05-28-1139-ChrVldr-AR...
by christian viladrich
Fri Sep 22, 2023 7:11 pm
Forum: This is SolarChat !!
Topic: H-alpha and Ca-H -- SHG close up images, 21 Sept
Replies: 16
Views: 1196

Re: H-alpha and Ca-H -- SHG close up images, 21 Sept

Amazing images Doug ! Resolution and processing are fantastic.

Maybe the first time these features are seen in a SHG image.
by christian viladrich
Fri Sep 22, 2023 2:27 pm
Forum: This is SolarChat !!
Topic: Maksutoc-Cassegrain Suitability
Replies: 17
Views: 1036

Re: Maksutoc-Cassegrain Suitability

Hi Brian,

Maksutov-Gregory (SW, Celestron, ...) are quite bad in blue, but Maktutov-Rumak (Intes) are quite good :

http://astrosurf.com/viladrich/astro/in ... ak/Mak.htm

So it all depends whether it is a Gregory or a Rumak. Which model are your considering ?
by christian viladrich
Thu Sep 21, 2023 12:03 pm
Forum: This is SolarChat !!
Topic: Inverted & colorized CaK images
Replies: 13
Views: 762

Re: Inverted & colorized CaK images

Hello Sai, May I suggest you reduce a little bit deconvolution (or equivalent). Indeed, if we carefully look at the gray scale image, we can see that the solar disk is coverered by small black spots. All of these are artefacts. For example, you can have a look at what the solar surface really looks ...
by christian viladrich
Thu Sep 21, 2023 11:51 am
Forum: This is SolarChat !!
Topic: CaK spots and proms 9th Sept
Replies: 11
Views: 1448

Re: CaK spots and proms 9th Sept

Well done, with a nice processing, in particular the transition between the disk, chromospheric fringe and prominences !
The resolution is quite good too.
And nice trick to handle ghost images !
by christian viladrich
Tue Sep 19, 2023 7:18 pm
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: Measurement of a DayStar PE 0.6 A
Replies: 23
Views: 3117

Re: Measurement of a DayStar PE 0.6 A

To put things in perspective, here are some examples of image obtained with this filter and a Hat8" :

https://www.flickr.com/photos/45136795@ ... 605283841/

https://www.flickr.com/photos/45136795@ ... 605283841/
by christian viladrich
Tue Sep 19, 2023 5:46 pm
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: Measurement of a DayStar PE 0.6 A
Replies: 23
Views: 3117

Re: Measurement of a DayStar PE 0.6 A

That doesn’t seem like it is within spec. I’d want my money back!😡 Think of all the customers that don’t have the ability to measure their etalon. At what f-ratio did you test it or does this not apply with how you measure? Do you have any recent images with it? You said it all. Not all the custome...