Etalon info for beginners
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Etalon info for beginners
Hi Folks
I have been asked for a link to info on etalons in general ... say air spaced v solid or just
a general understanding of bandwidths and how etalons operate.
If anyone can advise on some info on here then that would be great
Would be good for me to read as well
Thanks .... Brian
I have been asked for a link to info on etalons in general ... say air spaced v solid or just
a general understanding of bandwidths and how etalons operate.
If anyone can advise on some info on here then that would be great
Would be good for me to read as well
Thanks .... Brian
" Gentlemen only ever use Refractors "
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Re: Etalon info for beginners
Check out C. Viladrich website
http://www.astrosurf.com/viladrich/
Analysis of mica spaced Ha Fabry-Perot etalons
http://www.astrosurf.com/viladrich/astr ... lar/FP.htm
http://www.astrosurf.com/viladrich/
Analysis of mica spaced Ha Fabry-Perot etalons
http://www.astrosurf.com/viladrich/astr ... lar/FP.htm
Pedro Re'
https://pedroreastrophotography.com/
https://pedroreastrophotography.com/
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Re: Etalon info for beginners
Thanks Pedro
I have looked at Christians site before but I don't think it's necessarily for beginners though.
Brian
I have looked at Christians site before but I don't think it's necessarily for beginners though.
Brian
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Re: Etalon info for beginners
Hi
The PST shows a whole Sun view with prominences visible.
For visual on Prominences my M180 PST Stage 2 Mod shows brighter more contrasty images than a Daystar Quark I recently bought.
Issue is a small sweet spot and ghosts off the PST etalon, you have to rotate the etalon in the focusser to move away.
Even with a 180mm aperture I get best images with 25mm eyepiece.
The Quark has a circular polarizer in to remove ghost images but it dims the result. Other manufacturers Lunt? do not put in a filter but users complain about the ghosts and lack of light when they fit polarisers.
For a Quark with 4.2x Barlow in I reduced a 102mm F5 Skywatcher/Celestron OTA to be similar to the DS60 OTA Fno 3.5 and fl 350mm and the view improved because of the extra light going through the etalon. Somewhere between the original Quark and my M180 mod for the proms. Detectability is the square of intensity.
Using a little front etalon as an internal etalon inside a bigger OTA modification gets you brighter bigger images but at a cost in terms of the size of a 'sweet spot' for the PST or bandwidth changes across a solid etalon.
Andrew.
The PST shows a whole Sun view with prominences visible.
For visual on Prominences my M180 PST Stage 2 Mod shows brighter more contrasty images than a Daystar Quark I recently bought.
Issue is a small sweet spot and ghosts off the PST etalon, you have to rotate the etalon in the focusser to move away.
Even with a 180mm aperture I get best images with 25mm eyepiece.
The Quark has a circular polarizer in to remove ghost images but it dims the result. Other manufacturers Lunt? do not put in a filter but users complain about the ghosts and lack of light when they fit polarisers.
For a Quark with 4.2x Barlow in I reduced a 102mm F5 Skywatcher/Celestron OTA to be similar to the DS60 OTA Fno 3.5 and fl 350mm and the view improved because of the extra light going through the etalon. Somewhere between the original Quark and my M180 mod for the proms. Detectability is the square of intensity.
Using a little front etalon as an internal etalon inside a bigger OTA modification gets you brighter bigger images but at a cost in terms of the size of a 'sweet spot' for the PST or bandwidth changes across a solid etalon.
Andrew.
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Re: Etalon info for beginners
Hi Brian,Solar B wrote: ↑Sat May 16, 2020 8:48 am Hi Folks
I have been asked for a link to info on etalons in general ... say air spaced v solid or just
a general understanding of bandwidths and how etalons operate.
If anyone can advise on some info on here then that would be great
Would be good for me to read as well
Thanks .... Brian
Maybe here https://en.wikipedia.org/wiki/Fabry%E2% ... rferometer
regards Rainer
Observatorio Real de 14
San Luis Potosi Mexico
North 22° West 101°
Observatorio Real de 14
San Luis Potosi Mexico
North 22° West 101°
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Re: Etalon info for beginners
Many Thanks All
But I'm still looking for something that's perhaps a little less highbrow if possible ?
Brian
But I'm still looking for something that's perhaps a little less highbrow if possible ?
Brian
" Gentlemen only ever use Refractors "
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Re: Etalon info for beginners
These articles by Colin Kaminski might be helpful:
https://www.cloudynights.com/articles/c ... lons-r1729
https://www.cloudynights.com/articles/c ... logy-r1943
John
https://www.cloudynights.com/articles/c ... lons-r1729
https://www.cloudynights.com/articles/c ... logy-r1943
John
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Re: Etalon info for beginners
Thanks John
I had read Colinskis detailed reports before but had long since forgotten about
them
Brian
I had read Colinskis detailed reports before but had long since forgotten about
them
Brian
Last edited by Solar B on Tue May 19, 2020 3:33 pm, edited 1 time in total.
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Re: Etalon info for beginners
Think I might put this in the reference library when the topic goes quiet, a useful post to start Brian.
http://brierleyhillsolar.blogspot.co.uk/
Solar images, a collection of all the most up to date live solar data on the web, imaging & processing tutorials - please take a look!
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Re: Etalon info for beginners
In my recent book “Imaging Sunlight” - Springer there’re a good chapter on the etalon function and current available solar filters.
"Astronomical Spectroscopy - The Final Frontier" - to boldly go where few amateurs have gone before
https://groups.io/g/astronomicalspectroscopy
http://astronomicalspectroscopy.com
"Astronomical Spectroscopy for Amateurs" and
"Imaging Sunlight - using a digital spectroheliograph" - Springer
https://groups.io/g/astronomicalspectroscopy
http://astronomicalspectroscopy.com
"Astronomical Spectroscopy for Amateurs" and
"Imaging Sunlight - using a digital spectroheliograph" - Springer
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Re: Etalon info for beginners
Diagonally parked in a parallel universe.
Curiosity is the father of knowledge; uncertainty is the mother of wisdom.
Dark-Sky Defenders
Goldendale Observatory
Curiosity is the father of knowledge; uncertainty is the mother of wisdom.
Dark-Sky Defenders
Goldendale Observatory
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Re: Etalon info for beginners
https://www.hpb.com/products/imaging-th ... 3319248721
Is this the book Ken ?
And thanks Bob ..... great to hear from you to
Oh and I had long since forgotten about that CN thread also ....... my relatively insignificant thread
has turned into something quite significant to me
Brian
Is this the book Ken ?
And thanks Bob ..... great to hear from you to
Oh and I had long since forgotten about that CN thread also ....... my relatively insignificant thread
has turned into something quite significant to me
Brian
" Gentlemen only ever use Refractors "