Search found 4059 matches

by Valery
Wed Jan 03, 2024 5:01 pm
Forum: This is SolarChat !!
Topic: new Hi-res photospheric telescope
Replies: 76
Views: 5341

Re: new Hi-res photospheric telescope

I think, Valery, that you are wrong that I am looking for some arguments for Soley. On the contrary, I have the feeling that you are looking for arguments against it from the beginning. It should be noted that there are not hundreds of thousands of C14 owners. It's not a cheap telescope. Those who ...
by Valery
Sun Dec 31, 2023 2:37 am
Forum: This is SolarChat !!
Topic: new Hi-res photospheric telescope
Replies: 76
Views: 5341

Re: new Hi-res photospheric telescope

I feel, Valery, that no one here disputes the theoretical fact that the angular resolution increases with the diameter of the mirror. But as usual, the theory applies to the ideal state, but in practice other factors are applied that influence the result. Agreed. No one doubts the resolution apertu...
by Valery
Sun Dec 31, 2023 2:06 am
Forum: This is SolarChat !!
Topic: new Hi-res photospheric telescope
Replies: 76
Views: 5341

Re: new Hi-res photospheric telescope

1. Why would anyone go to the trouble of making a mirror with L/16 if they could get the same image with L/2? 2. The quality of the resulting image is limited by the theoretical resolution, but this does not mean that every telescope meets it. 3. I've seen solar photos from the TAK 150mm which hand...
by Valery
Sat Dec 30, 2023 3:17 pm
Forum: This is SolarChat !!
Topic: new Hi-res photospheric telescope
Replies: 76
Views: 5341

Re: new Hi-res photospheric telescope

We are aware of the outstanding capabilities of our telescope, and for other solar photographers, we are enthusiastically and experimentally building the best-optimised outstanding telescope for solar photography. Any your efforts will not change physics. Larger aperture has higher angular resoluti...
by Valery
Sat Dec 30, 2023 3:11 pm
Forum: This is SolarChat !!
Topic: new Hi-res photospheric telescope
Replies: 76
Views: 5341

Re: new Hi-res photospheric telescope

Laszlo, Can you, please, note for youself, that SCT telescope can be EASILY corrected in violet and UV spectral range? Is this so difficult to remember? Just like newtonians are corrected for coma with comacorrected barlow, with the same easy SCT can be corrected for coma and SA in violet and UV. So...
by Valery
Sat Dec 30, 2023 3:05 pm
Forum: This is SolarChat !!
Topic: new Hi-res photospheric telescope
Replies: 76
Views: 5341

Re: new Hi-res photospheric telescope

It is important to highlight that if you want to compare the image quality of telescopes, you do so at the same image processing level. In this pair of images there is no post-processing noise filtering (in either image), so you can see how much advantage solar newtons have over a non-solar telesco...
by Valery
Sat Dec 30, 2023 2:21 pm
Forum: This is SolarChat !!
Topic: new Hi-res photospheric telescope
Replies: 76
Views: 5341

Re: new Hi-res photospheric telescope

As for the SCT, unfortunately there are several parameters that do not allow the photo below to be taken with it easily or at all. One of these parameters is shown in the graph below, which displays that the Strehl in blue degrades extremely quickly on the C14. source: http://www.astrosurf.com/vila...
by Valery
Sat Dec 30, 2023 2:10 pm
Forum: This is SolarChat !!
Topic: new Hi-res photospheric telescope
Replies: 76
Views: 5341

Re: new Hi-res photospheric telescope

1. Why are off-axis Newtons built when you think central obstruction improves resolution? 2. I won't dispute the statement that the best possible C14 will be better than the best N300, but for mass production it is not so certain. 1. Central obstruction increases CONTRAST ON HIGHER SPATIAL FREQUENC...
by Valery
Sat Dec 30, 2023 1:49 pm
Forum: This is SolarChat !!
Topic: new Hi-res photospheric telescope
Replies: 76
Views: 5341

Re: new Hi-res photospheric telescope

It's a nice comparison, Valery, but it says nothing about the quality of the Newton's mirrors and collimation. It just shows that this particular N300 performed worse than the C14. Yes, it performs worser because of it's smaller diameter. And all other 300mm telescopes will perform worser due to th...
by Valery
Sat Dec 30, 2023 12:07 pm
Forum: This is SolarChat !!
Topic: new Hi-res photospheric telescope
Replies: 76
Views: 5341

Re: new Hi-res photospheric telescope

DeepSolar64 wrote: Sat Dec 30, 2023 6:30 am Those C14 images are awesome also!!

Maybe a 14" SolEye would be a possibility?
Yes. Soleye must be of 14" diameter to be equal to a C14 in angular resolution.


Valery
by Valery
Fri Dec 29, 2023 8:27 pm
Forum: This is SolarChat !!
Topic: new Hi-res photospheric telescope
Replies: 76
Views: 5341

Re: new Hi-res photospheric telescope

I don't care about the contrast, Valery. I vividly remember the increase in resolution and detail when I swapped out the 42mm L/6 secondary mirror on the N180/F7 for a 33mm L/20. Even a blind person would know the difference. I think the optics on the N300 can be purchased in much better quality th...
by Valery
Thu Dec 28, 2023 12:18 am
Forum: This is SolarChat !!
Topic: new Hi-res photospheric telescope
Replies: 76
Views: 5341

Re: new Hi-res photospheric telescope

pupak wrote: Wed Dec 27, 2023 5:56 pm If the solar N300 will be a special with a significantly smaller central obstruction similar to the MN from INTES, it may ultimately beat the C14.
Never. Aperture rules. Larger central obstruction makes contrast on highest spatial frequencies higher vs smaller c.o.
by Valery
Wed Dec 27, 2023 4:28 pm
Forum: This is SolarChat !!
Topic: new Hi-res photospheric telescope
Replies: 76
Views: 5341

Re: new Hi-res photospheric telescope

A comparison between the two scopes (C14 - solar newton) was made by Christian Viladrich himself formely in 2018, when they captured the Sun from the same place at the same time with Thierry Leagult. It is really interesting and useful to read this thread: https://solarchatforum.com/viewtopic.php?t...
by Valery
Tue Dec 26, 2023 10:40 pm
Forum: This is SolarChat !!
Topic: new Hi-res photospheric telescope
Replies: 76
Views: 5341

Re: new Hi-res photospheric telescope

I think it's a great opportunity to discuss a hidden difficulty and potential of solar photography. However, I must add, I did not want to speak against a certain type of telescope. I read by my own eyes that you wrote that this telescope - Soleye 300 achieved better resolution than 356mm C14. You ...
by Valery
Tue Dec 26, 2023 6:12 pm
Forum: This is SolarChat !!
Topic: new Hi-res photospheric telescope
Replies: 76
Views: 5341

Re: new Hi-res photospheric telescope

"The Soleye 300 is fully capable of hi-res Ca-K photography which means it also achieves higher resolutions than the C14. "(С) What about the laws of physics? Are they no longer valid? Or maybe this is a typo and you meant the C11 scope? If not a typo, solid poofs required. Valery Hi Vale...
by Valery
Tue Dec 26, 2023 12:44 pm
Forum: This is SolarChat !!
Topic: new Hi-res photospheric telescope
Replies: 76
Views: 5341

Re: new Hi-res photospheric telescope

Can you clarify a bit? Which country or countries did you mean? Thanks, Valery I don't know the conditions in other countries, so I'm writing about the Czech Republic, where I live. In various areas of interest, forums are created around which the community is centered. If such a forum is controlle...
by Valery
Tue Dec 26, 2023 3:04 am
Forum: This is SolarChat !!
Topic: new Hi-res photospheric telescope
Replies: 76
Views: 5341

Re: new Hi-res photospheric telescope

pupak wrote: Wed Dec 13, 2023 8:58 pm
It is important not to do business in a country where the astronomical community is controlled by the mafia, then you can do a lot. Unfortunately, this is not possible here in the Czech Republic.
Petr,

Can you clarify a bit? Which country or countries did you mean?

Thanks,


Valery
by Valery
Tue Dec 26, 2023 2:36 am
Forum: This is SolarChat !!
Topic: new Hi-res photospheric telescope
Replies: 76
Views: 5341

Re: new Hi-res photospheric telescope

"The Soleye 300 is fully capable of hi-res Ca-K photography which means it also achieves higher resolutions than the C14. "(С)

What about the laws of physics? Are they no longer valid? Or maybe this is a typo and you meant the C11 scope?
If not a typo, solid poofs required.


Valery
by Valery
Sun Dec 24, 2023 6:12 pm
Forum: This is SolarChat !!
Topic: New Solar Prediction Update and Experimental Display
Replies: 10
Views: 916

Re: New Solar Prediction Update and Experimental Display

Thank you very much, Bob.


Valery
by Valery
Wed Nov 15, 2023 9:18 am
Forum: This is SolarChat !!
Topic: Looking for opinion on corona processing
Replies: 15
Views: 892

Re: Looking for opinion on corona processing

Took a next look at them and now #2 is the best for me.
by Valery
Mon Nov 13, 2023 9:39 am
Forum: This is SolarChat !!
Topic: Saturday Sunshine 11th November
Replies: 21
Views: 1023

Re: Saturday Sunshine 11th November

Mark,

I believe that at least a 100mm for the Ha line can be used for larger scale with the same success.
Other than this, the works are great.


Valery
by Valery
Mon Nov 13, 2023 9:33 am
Forum: This is SolarChat !!
Topic: Looking for opinion on corona processing
Replies: 15
Views: 892

Re: Looking for opinion on corona processing

#4 - best for my monitor and eyes/brain.
by Valery
Tue Nov 07, 2023 1:53 pm
Forum: This is SolarChat !!
Topic: Solar details H-a 06.11.
Replies: 11
Views: 531

Re: Solar details H-a 06.11.

pupak wrote: Tue Nov 07, 2023 11:20 am the ones with the smallest form the pebbles. Spatially, I would guess that they will be closer to the center of the Sun.
Why you think so?


Valery
by Valery
Sun Oct 22, 2023 3:38 pm
Forum: This is SolarChat !!
Topic: David and Goliath - ISTAR 9"/F9 and Sollar scout DSII40mm
Replies: 20
Views: 2693

Re: David and Goliath - ISTAR 9"/F9 and Sollar scout DSII40mm

Just to chime in on my experience with an ISTAR 150mm f/10. I had it independently tested. I won’t bore you with the details, but in summary it has ~ 1/5 PV coma at full aperture (it is advertised as a minimum of 1/4 wave) , and is ~ 1/10 wave at 120mm. Essentially no astigmatism. It is “well polis...
by Valery
Fri Oct 20, 2023 5:31 am
Forum: Annular Solar Eclipse October 14 2023
Topic: Montage of Moon approaching Sun in front of corona
Replies: 24
Views: 4088

Re: Montage of Moon approaching Sun in front of corona

George, for me your series of images is a SPOY! Yes, SPOY!

Valery
by Valery
Fri Oct 20, 2023 5:03 am
Forum: Annular Solar Eclipse October 14 2023
Topic: Montage of Moon approaching Sun in front of corona
Replies: 24
Views: 4088

Re: Montage of Moon approaching Sun in front of corona

DeepSolar64 wrote: Fri Oct 20, 2023 2:04 am I thought that might have been an AM5 mounted on the Losmandy tripod.
Ditto!


Valery.
by Valery
Mon Oct 16, 2023 6:04 am
Forum: Annular Solar Eclipse October 14 2023
Topic: Moon approaching Sun over corona before first contact
Replies: 17
Views: 2717

Re: Moon approaching Sun over corona before first contact

Fantastic image, George!

Did you this photo intentionally to show the moon on the corona background?

Very unique photo! A 100% SPOD !


Valery
by Valery
Sun Oct 15, 2023 7:05 pm
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: Measurement of a very good Quark
Replies: 4
Views: 1699

Re: Measurement of a very good Quark

You are completely right Valery ! Good would mean : - narrow FWHM, - good uniformity of the CWL (assuming that if we have uniformity of the CWL, we also have uniformity of the FWHM ...), - a good transmission (to keep exposure short). I measure FWHM only at the center of the filter. I have indicati...
by Valery
Thu Oct 12, 2023 4:55 pm
Forum: Solar Radio, Magnetometry and Spectroscopy
Topic: Sol’Ex Spectroheliograph first light (FS60C F/5.9) | (20231012)
Replies: 19
Views: 2639

Re: Sol’Ex Spectroheliograph first light (FS60C F/5.9) | (20231012)

Excellent debute in the SHG league, Pedro! Congratulates!

BTW. I believe with Portugal excellent seeing, in the future, the minimum of aperture should be 150mm. Correct?

Looking for many more images from you.


Valery
by Valery
Thu Sep 21, 2023 11:15 pm
Forum: SPoD Archive
Topic: H-alpha and Ca-H -- SHG close up images, 21 Sept
Replies: 7
Views: 778

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

Fantastic! Congratulates, Doug!

Fibrills are significantly better seen in Ca-H vs Ca-K.

A lot of similarities between Ha and Ca-H pictures.

Should be in SPOD.

Valery
by Valery
Thu Sep 21, 2023 11:15 pm
Forum: This is SolarChat !!
Topic: H-alpha and Ca-H -- SHG close up images, 21 Sept
Replies: 16
Views: 1184

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

Fantastic! Congratulates, Doug!

Fibrills are significantly better seen in Ca-H vs Ca-K.

A lot of similarities between Ha and Ca-H pictures.

Should be in SPOD.

Valery
by Valery
Wed Sep 20, 2023 8:33 am
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: Reducers for 393nm Wavelength?
Replies: 7
Views: 1156

Re: Reducers for 393nm Wavelength?

I asked Baader about using the RG 0.4 and 0.7 focal reducers intended to be used for the TZ3 focal reducers. They responded: "We actually haven't tried it out yet, as a reducer usually is not necessary for the CaK-filter (which operates at the native f/ratio of the tellescope), and the SolarSp...
by Valery
Mon Sep 18, 2023 1:21 am
Forum: This is SolarChat !!
Topic: Corona from 16 September 2023
Replies: 8
Views: 332

Re: Corona from 16 September 2023

Brilliant results, George! Fantastic!

Valery
by Valery
Fri Sep 15, 2023 10:04 am
Forum: SPoD Archive
Topic: First attempt with a Ca K 1 A filter and a 300 mm Newtonian
Replies: 16
Views: 1206

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

Maybe the SHG is equivalent to a triple-stack 1 A combination. Just a guess ... If at 0.1A filter you do mean the filter made of Apollo's batch, then no, Christian, they are not an equivalent of the 0.2A SHG. Even quad stack of them is FAR not equivalent. I saw images of quad stack. You need a doub...
by Valery
Fri Sep 15, 2023 10:04 am
Forum: This is SolarChat !!
Topic: First attempt with a Ca K 1 A filter and a 300 mm Newtonian
Replies: 25
Views: 2361

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

Maybe the SHG is equivalent to a triple-stack 1 A combination. Just a guess ... If at 1A filter you do mean the filter made out of Apollo's batch, then no, Christian, they are not an equivalent of the 0.2A SHG. Even quad stack of them is FAR not equivalent. I saw images of quad stack of these filte...
by Valery
Thu Sep 14, 2023 4:17 am
Forum: This is SolarChat !!
Topic: First light with new toy - iStar Asteria TCR 204-12 R35
Replies: 27
Views: 1328

Re: First light with new toy - iStar Asteria TCR 204-12 R35

I wish I would have bought a Chromacor when they were available new. Now they are hard to find. They would really help my 102mm achromat, especially at night. Baader does make two filters to reduce chromatic aberration. Their Fringe Killer and the Semi-Apo filters. They screw into the eyepiece or d...
by Valery
Tue Sep 12, 2023 2:25 pm
Forum: This is SolarChat !!
Topic: First light with new toy - iStar Asteria TCR 204-12 R35
Replies: 27
Views: 1328

Re: First light with new toy - iStar Asteria TCR 204-12 R35

Thank you very much Dennis, Mark, James, Petr, Clare Peter, Franco, Vin, Christian and Simon for all your kind comments! Mark: With the Losmandy dovetail, which is quite heavy, it weighs in at 22kg. Then comes ERF, filter and camera, so it's definetely pushing the weight limits of the AM5. Then the...
by Valery
Sun Sep 10, 2023 11:02 am
Forum: This is SolarChat !!
Topic: AR210/F9 and best seeing of this year 09.09.
Replies: 11
Views: 600

Re: AR210/F9 and best seeing of this year 09.09.

Photos # 1, 4, 8, 9 are truly amazing. They took a well deserved place in my collection of H-a solar images taken by other amateurs with 8" apertures. Excellent seeing is at least 2/3 of the job. And 8-9/10 of the job in CaK.

Thanks for sharing, Petr.


Valery
by Valery
Thu Sep 07, 2023 7:14 am
Forum: Commercial Solar Filters/Cameras/Hardware
Topic: Measurement of a very good Quark
Replies: 4
Views: 1699

Re: Measurement of a very good Quark

Very interesting, Christian.

Any images of the sun with this Quark?

Telling "good Quark", what did you mean - the Quark is very uniform, the Quark is narrow enough, or the Quarl is a very uniform and narrow enough?


Valery
by Valery
Thu Sep 07, 2023 6:57 am
Forum: This is SolarChat !!
Topic: One wild prominence and a few details 05.09.
Replies: 6
Views: 337

Re: One wild prominence and a few details 05.09.

The very first picture (colorized) is very dramatic and well worth of APOD, IMHO. Such pictures are really rare.


Valery
by Valery
Sun Aug 27, 2023 5:55 am
Forum: This is SolarChat !!
Topic: Cycle 25 progression
Replies: 26
Views: 1809

Re: Cycle 25 progression

Thanks, Stu! Excellent work. Much appreciated.


Valery
by Valery
Wed Aug 23, 2023 4:53 am
Forum: This is SolarChat !!
Topic: Some closeups of todays sun in Ca-K
Replies: 15
Views: 594

Re: Some closeups of todays sun in Ca-K

Oh my!!!!!! almost professional :bow :bow :bow Alexandra Images are indeed very good. Just need a bit better seeing, IMHO. But you can do the same or even better if you will use the same imaging train as Dennis did. You have a telescope which is 11" and so, potentially it can deliver even bett...
by Valery
Wed Aug 23, 2023 4:46 am
Forum: This is SolarChat !!
Topic: Coronado BF30 - diagonal not needed? & BF preservation?
Replies: 5
Views: 380

Re: Coronado BF30 - diagonal not needed? & BF preservation?

Use this equipment as written on it: telescope with both etalons --> internal BF --> diagonal with a red filter. This all.

In your case internal BF + red glass diagonal = complete BF.
by Valery
Wed Aug 23, 2023 4:30 am
Forum: SPoD Archive
Topic: WL AR 3504
Replies: 10
Views: 1132

Re: WL AR 3504

Nice image, Daniel!


Valery
by Valery
Wed Aug 23, 2023 4:30 am
Forum: This is SolarChat !!
Topic: WL AR 3504
Replies: 12
Views: 501

Re: WL AR 3504

Nice image, Daniel!


Valery
by Valery
Sat Aug 19, 2023 8:06 am
Forum: This is SolarChat !!
Topic: My woes with a Solar full disk in H-a 16.08.
Replies: 20
Views: 898

Re: My woes with a Solar full disk in H-a 16.08.

Hey Petr, when you are recording are you using neutral gamma on the camera? I have no idea what it is. Teach me. I finally got the IMX178 today so I tried FD with it. It looks like this chip will be perfect for my telescope. This image is really better (uniformity wise) than the first one. However ...
by Valery
Thu Aug 17, 2023 6:49 am
Forum: This is SolarChat !!
Topic: My woes with a Solar full disk in H-a 16.08.
Replies: 20
Views: 898

Re: My woes with a Solar full disk in H-a 16.08.

The only really good DS of FD images I saw, all were taken with both etalons external. All other combinations more or less suffer of contrast and brightness nonuniformity. Best of them were done by Bob Yoesly with his two SM90 pre-Meade selected and precisely clocked. Quarks have their own vignettin...
by Valery
Sat Aug 05, 2023 11:15 pm
Forum: This is SolarChat !!
Topic: Solar corona from August 1
Replies: 31
Views: 1781

Re: Solar corona from August 1

Valery, thanks. I am limiting my aperture to the following extent. Many thanks, George. PS. If memory serves me well, I remember that B. Liot has used the touth of skin fat from the side of the nose and polished the lens with a piece of lint-free flannel. Honestly, I can't imagine how this helped L...
by Valery
Sat Aug 05, 2023 6:18 am
Forum: This is SolarChat !!
Topic: Solar corona from August 1
Replies: 31
Views: 1781

Re: Solar corona from August 1

Hi, Valery. I may very well have it wrong, but let me explain what I am saying more clearly and see what you and others think. Hi George, Clear enough. I forgot about the fact that coatings are a very strong source of a light scattering. My fault. OK, we need to work behind the occulting disk. To k...
by Valery
Fri Aug 04, 2023 8:19 pm
Forum: This is SolarChat !!
Topic: Solar corona from August 1
Replies: 31
Views: 1781

Re: Solar corona from August 1

christian viladrich wrote: Fri Aug 04, 2023 6:15 pm Not sure if this is relevant to the discussion, but the FWHM of the Fe XIV line is about 0.9 A (source : S. Koutchmy CNRS/IAP).
Close to H-a.
Should be enough for imaging of a 1 degree circle if the filter is about 0.7A FWHM and mounted in a front of the objective.


Valery