I checked with Christian on this; here's his reply:
"The work of the book is advancing at a slow pace for a number of reasons. I think we will have it ready by the end of the first semester of 2020... We have included a lot of new stuff compared to the French version."
Search found 644 matches
- Wed Dec 11, 2019 1:32 am
- Forum: Solar Astronomy Shop and Swap
- Topic: "Astronomie Solaire" - New (French) book on Solar Observation now available
- Replies: 35
- Views: 14483
- Sun Dec 01, 2019 12:28 am
- Forum: This is SolarChat !!
- Topic: Coronado PST testing
- Replies: 31
- Views: 8128
Re: Coronado PST testing
Hi Alexandra, I too think I prefer the old PST image, even though it is dimmer - it appears a bit more uniform. Just a thought - have you checked the ITF for rust? Replacing it in the older PST might give you a considerable bump in brightness. Better yet, using a Baader 35 nm Ha filter as an objecti...
- Fri Nov 22, 2019 2:40 pm
- Forum: Solar Scope Modifications
- Topic: Removal of lunt erf double stack possible?
- Replies: 3
- Views: 2476
Re: Removal of lunt erf double stack possible?
Double stacking reduces the overall transmission of the filter system, but also removes the parasitic continuum from the photosphere itself. Both contribute to the overall perception of reduced image brightness, but vastly improved disc contrast. For two Lunt etalons in series with a transmission of...
- Fri Oct 25, 2019 4:28 pm
- Forum: Commercial Solar Filters/Cameras/Hardware
- Topic: Lunt monster
- Replies: 14
- Views: 4971
Re: Lunt monster
Agreed Mark, Indeed it would theoretically be even smaller, since the FWHM of the PST is generrally closer to 0.1 nm, and a double stacked air spaced etalon is less than 0.05 nm; the Jacquinot spot is proportional to the square root of 2 x the FWHM.
- Wed Oct 23, 2019 1:55 pm
- Forum: Commercial Solar Filters/Cameras/Hardware
- Topic: Lunt monster
- Replies: 14
- Views: 4971
Re: Lunt monster
Just visited with Brian at Lunt where this telescope is located... an impressive instrument when seen up close and personal. Objective has ERF coatings. Middle section has a large tilted precision polished optical window with additional ERF coatings. Open tube design in order to prevent build-up of ...
- Wed Oct 23, 2019 1:28 pm
- Forum: This is SolarChat !!
- Topic: When I win the lottery
- Replies: 20
- Views: 2711
Re: When I win the lottery
Just visited with Brian at Lunt where this telescope is located... an impressive instrument when seen up close and personal. Objective has ERF coatings. Middle section has a large tilted precision polished optical window with additional ERF coatings. Open tube design in order to prevent build-up of ...
- Wed Oct 23, 2019 1:01 pm
- Forum: Commercial Solar Filters/Cameras/Hardware
- Topic: Time for selling...
- Replies: 11
- Views: 3872
Re: Time for selling...
That is indeed a rather old citation, and one must take most predictions with a grain of salt. One of the most respected sources for solar information is Dr. David Hathaway, who is now retired from NASA, but who maintains an active solar prediction interest with solar physicist Lisa Upton: We predic...
- Mon Aug 19, 2019 9:57 pm
- Forum: Solar Scope Modifications
- Topic: Blocking Filter In a Collimated Beam?
- Replies: 10
- Views: 3253
Re: Blocking Filter In a Collimated Beam?
"Anyone ever tried placing a Coronado / Lunt blocking filter in a collimated beam to see if it trims down continuum leakage in the wings?" Hi Mark, not sure this would get much improvement. If the BF has a Lorentzian profile - just as with FP etalons - the main effect would be to improve field angl...
- Wed Jul 31, 2019 5:47 pm
- Forum: Solar Scope Modifications
- Topic: asi120mm-s DIY cooling
- Replies: 6
- Views: 2678
Re: asi120mm-s DIY cooling
Did this with my Chameleon a few years back:
https://www.cloudynights.com/topic/3266 ... chameleon/
I would consider active cooling for about any camera employed during the day for solar imaging.
https://www.cloudynights.com/topic/3266 ... chameleon/
I would consider active cooling for about any camera employed during the day for solar imaging.
- Tue Jul 02, 2019 9:35 pm
- Forum: This is SolarChat !!
- Topic: Tuesday Morning Sunshine - 2nd July
- Replies: 7
- Views: 900
Re: Tuesday Morning Sunshine - 2nd July
Very nice images Mark! What generation of SM90 do you have? Just an etalon/BF or the whole SM scope?
For your DS images I'm assuming you're using the telecentric version. Has anyone tried the Combo version for DSing?
For your DS images I'm assuming you're using the telecentric version. Has anyone tried the Combo version for DSing?
- Sat Jun 15, 2019 5:34 pm
- Forum: Commercial Solar Filters/Cameras/Hardware
- Topic: Help me to know what is that...
- Replies: 3
- Views: 2190
Re: Help me to know what is that...
Those appear to be either Newton's rings or FP etalon interference fringes: https://en.wikipedia.org/wiki/Newton%27s_rings https://en.wikipedia.org/wiki/Fabry%E2%80%93P%C3%A9rot_interferometer They could be an internal reflection issue with your imaging system, or there might be something amiss with...
- Fri Jun 07, 2019 4:36 pm
- Forum: Solar Scope Modifications
- Topic: Relation between BF size and the PST Sweet Spot
- Replies: 8
- Views: 2806
Re: Relation between BF size and the PST Sweet Spot
No, not true. The "sweet spot," technically known as the Jacquinot spot, is generated by the field angles (and for the mica filters - instrument angles) produced by the optical configuration within which the etalon is placed. For collimator based etalon systems, it has little to do with the f ratios...
- Sun Apr 28, 2019 12:18 pm
- Forum: This is SolarChat !!
- Topic: Hydrogen Alpha Upgrade
- Replies: 19
- Views: 2016
Re: Hydrogen Alpha Upgrade
Good luck with your journey David - but I did want to get back to you about your question: " Fascinating Bob. So a question then, of the front mounted etalons on the market are some generally better than others e.g. Coronado vs Lunt vs Solarscope vs ?? Or do the variations in each make it pretty muc...
- Sun Apr 28, 2019 11:52 am
- Forum: This is SolarChat !!
- Topic: Photographic Benefits of UV/IR Blocking Filter
- Replies: 10
- Views: 1208
Re: Photographic Benefits of UV/IR Blocking Filter
I have seen first hand that if something can go wrong, it will eventually actually go wrong - at least for someone. So when it comes to safety, I'm pretty conservative. I also believe there is a reason most solar telescope OEM's incorporate IR blocking as a safety AND liability issue. Here's a slide...
- Fri Apr 26, 2019 9:53 pm
- Forum: This is SolarChat !!
- Topic: Hydrogen Alpha Upgrade
- Replies: 19
- Views: 2016
Re: Hydrogen Alpha Upgrade
" Front mounted etalons are fickle and unreliable in terms of their performance - I have been through and own quite a few; a couple of them are lovely and flat, and show no banding etc due to needing excess tilt. Then there are quite a lot that do have banding and especially with imaging more so sho...
- Wed Apr 24, 2019 5:35 pm
- Forum: This is SolarChat !!
- Topic: Lunt CaK module testing 22nd April
- Replies: 24
- Views: 1934
Re: Lunt CaK module testing 22nd April
Hi Valery, I don't think it is valid to apply processing to only one image and not the other to come to a conclusion that the questionable filter has no faults. Under the circumstances of using identical scopes, camera, and processing to obtain the images, the significant differences between the two...
- Wed Apr 24, 2019 11:37 am
- Forum: This is SolarChat !!
- Topic: Lunt CaK module testing 22nd April
- Replies: 24
- Views: 1934
Re: Lunt CaK module testing 22nd April
Hi Alexandra, I noticed you called yours a "Lunt CaK wedge." I'm assuming that means it's the B1800 diagonal, and therefore the diagonal mirror itself might be a part of the problem. If you are beyond the Lunt 5 year warranty and end up stuck with it (and since you likely do only imaging for CaK any...
- Wed Apr 24, 2019 11:10 am
- Forum: This is SolarChat !!
- Topic: Hydrogen Alpha Upgrade
- Replies: 19
- Views: 2016
Re: Hydrogen Alpha Upgrade
You've covered all the bases David.
Front etalon(s) will generally give you the best performance - especially for full disc views/imaging, and of course will cost the most...
Front etalon(s) will generally give you the best performance - especially for full disc views/imaging, and of course will cost the most...
- Sun Apr 21, 2019 7:29 pm
- Forum: Solar Scope Modifications
- Topic: PST Etalon with a Quark, Log & Results
- Replies: 115
- Views: 21587
Re: PST Etalon with a Quark, Log & Results
That's really very good Marty, and better than a lot of others I've seen with the more recently made filter systems.
- Mon Apr 15, 2019 1:19 am
- Forum: This is SolarChat !!
- Topic: When I win the lottery
- Replies: 20
- Views: 2711
Re: When I win the lottery
Here's the skinny from Lunt: https://mailchi.mp/luntsolarsystems/join-us-at-neaf-and-double-stack-your-savings-save-10-off-gift-cards-starting-now-2205613?e=657ad57360 Intriguing for the ability to do "full disc" imaging - which indeed would require very large etalons to keep the Jacquinot spot larg...
- Mon Apr 15, 2019 12:57 am
- Forum: Commercial Solar Filters/Cameras/Hardware
- Topic: First solar shot ASI290
- Replies: 10
- Views: 3097
Re: First solar shot ASI290
Looks great George!
- Sun Apr 14, 2019 7:22 pm
- Forum: Commercial Solar Filters/Cameras/Hardware
- Topic: Help tweak this PST + SM40II Double Stack?
- Replies: 20
- Views: 4196
Re: Help tweak this PST + SM40II Double Stack?
Marty, I would be very careful about compression Richview tuning. 1) The DS etslons sometimes are farther to the red wing, and may require more compression to come on-hand with no tilt. 2) Going to the blue wing could apply too much pressure, stressing or fracturing the ERF (there are no collimating...
- Sun Apr 14, 2019 3:20 am
- Forum: Commercial Solar Filters/Cameras/Hardware
- Topic: Help tweak this PST + SM40II Double Stack?
- Replies: 20
- Views: 4196
Re: Help tweak this PST + SM40II Double Stack?
I would try the SM40 on its own on another small refractor. Leave the tilt alone (e.g. no tilt) and use the Richview only (compression - tightening) to tune the etalon. Add the etalon to the pre-tuned PST, and tilt the etalon just enough to get the reflections of the disc far enough to get the full ...
- Sat Apr 13, 2019 1:11 am
- Forum: Solar Scope Modifications
- Topic: Tilt needed on a front ERF?
- Replies: 2
- Views: 2115
Re: Tilt needed on a front ERF?
I recall the general parameter for both external and internal filter tilts is about 2 degrees.
- Sat Apr 06, 2019 9:14 pm
- Forum: Solar Scope Modifications
- Topic: Crazy Idea...?
- Replies: 4
- Views: 2263
Re: Crazy Idea...?
Removed.