Double Stack Lunt CaK filter
- Merlin66
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Double Stack Lunt CaK filter
Has anyone tried double stacking a Lunt CaK filter to reduce the bandwidth to around 1.2A?
(Using an old PST yellow filter doesn’t count - only current Lunt filters)
(Using an old PST yellow filter doesn’t count - only current Lunt filters)
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Re: Double Stack Lunt CaK filter
OK.
Do you use two B1800 filters? If so how do you join and align them.
Do you remove any of the secondary filter elements?
Photos?
Do you use two B1800 filters? If so how do you join and align them.
Do you remove any of the secondary filter elements?
Photos?
"Astronomical Spectroscopy - The Final Frontier" - to boldly go where few amateurs have gone before
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Re: Double Stack Lunt CaK filter
I used two B1800 filters. ill post a picture of the module tonight
This is the thread I followed (unfortunately the images of the set up have been removed)
viewtopic.php?t=8797
Comparison from last year (DS top and SS bottom). These are unprocessed images
SS DS by Torsinadoc, on Flickr
This is the thread I followed (unfortunately the images of the set up have been removed)
viewtopic.php?t=8797
Comparison from last year (DS top and SS bottom). These are unprocessed images
SS DS by Torsinadoc, on Flickr
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Re: Double Stack Lunt CaK filter
I took my most recent FD (taken 12-30) image cropped it added shadows and highlights, curves and gamma to bring out some proms. I exposed the original histogram to 80% and didn't try to capture proms. These were not faint. No sharpening was applied. I don't recall the original capture settings
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Re: Double Stack Lunt CaK filter
If there is anything specific you want me to test next time I can image let me know
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Re: Double Stack Lunt CaK filter
I would be interested in seeing a photo of the filter setup.
Also, if you could, at the next opportunity, collect an image in DS mode targeting any proms, recording the scope/ camera/ exposure/ stack and any other parameters.
With the SHG I can map the solar surface and the visibility of the proms across the whole CaK wavelength. I'm trying to establish a correlation between bandwidth, offset to CWL and the ease (or otherwise) of imaging proms.
I can obtain comparison images at approx 0.18A bandwidth every 0.2A across the K3/ K2/K1 regions. The K1 at +/- 1A shows sunspots and faculae similar to a single stack Lunt image (2.2A ) Proms and filaments very difficult. At K1 around +/- 0.5A starts to show more "flocculation" typical of a double stack system around 1A. Some filaments and proms. At K2, 0.2A from the CWL the surface texture is now showing the activity and filaments. Filaments and proms visible. Finally on the CaK central wavelength - texture more prominent, filaments and proms easily visible.
Obviously the wide bandwidth filters are a combination of all these wavelengths.
The recording of the proms is influenced by the significant background light with no prom detail found in the K1 regions, the wider the bandwidth the more difficult the proms.
Your SS images look like the K1 at 1A offset, and the DS shows similarities to K1 at 0.5A offset.
Ken
Also, if you could, at the next opportunity, collect an image in DS mode targeting any proms, recording the scope/ camera/ exposure/ stack and any other parameters.
With the SHG I can map the solar surface and the visibility of the proms across the whole CaK wavelength. I'm trying to establish a correlation between bandwidth, offset to CWL and the ease (or otherwise) of imaging proms.
I can obtain comparison images at approx 0.18A bandwidth every 0.2A across the K3/ K2/K1 regions. The K1 at +/- 1A shows sunspots and faculae similar to a single stack Lunt image (2.2A ) Proms and filaments very difficult. At K1 around +/- 0.5A starts to show more "flocculation" typical of a double stack system around 1A. Some filaments and proms. At K2, 0.2A from the CWL the surface texture is now showing the activity and filaments. Filaments and proms visible. Finally on the CaK central wavelength - texture more prominent, filaments and proms easily visible.
Obviously the wide bandwidth filters are a combination of all these wavelengths.
The recording of the proms is influenced by the significant background light with no prom detail found in the K1 regions, the wider the bandwidth the more difficult the proms.
Your SS images look like the K1 at 1A offset, and the DS shows similarities to K1 at 0.5A offset.
Ken
"Astronomical Spectroscopy - The Final Frontier" - to boldly go where few amateurs have gone before
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"Astronomical Spectroscopy for Amateurs" and
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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: Double Stack Lunt CaK filter
Here are the images. I needed to get an adapter since both ends were male. I assume I performed this mod correctly.
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- OlegLviv
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Re: Double Stack Lunt CaK filter
torsinadoc
very good!
Which telescope and camera you use?
very good!
Which telescope and camera you use?
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Baader D-ERF 160MM
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Telescope: TS 152/900/Bresser 102/1350
Baader D-ERF 160MM
2xBaader 1.25 GPC
2xLunt 50mm
Lunt Cak B1200
Coronado BF15
Camera: Apollo Max 432M/ Apollo Mini 429M/Player One Mars II 462M/QHY 290MM
Mounh: 2xSky Watcher AZEQ6
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Re: Double Stack Lunt CaK filter
102 f11 achromat masked to 60. If seeing allows I can get good results at full aperture. I use a zwo 1600 for FD and zwo 290 for close ups.
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Re: Double Stack Lunt CaK filter
Why you masked to 60mm? Because CAK love f20?torsinadoc wrote: ↑Fri Jan 28, 2022 9:02 am102 f11 achromat masked to 60. If seeing allows I can get good results at full aperture. I use a zwo 1600 for FD and zwo 290 for close ups.
https://www.facebook.com/oleg.lavigne/
https://www.astrobin.com/users/RamonLviv/
https://www.astroclub.kiev.ua/forum/ind ... ic=46758.0
Telescope: TS 152/900/Bresser 102/1350
Baader D-ERF 160MM
2xBaader 1.25 GPC
2xLunt 50mm
Lunt Cak B1200
Coronado BF15
Camera: Apollo Max 432M/ Apollo Mini 429M/Player One Mars II 462M/QHY 290MM
Mounh: 2xSky Watcher AZEQ6
Telecentric Lense: Televue Powermate 2/2.5x/4X/5X
https://www.astrobin.com/users/RamonLviv/
https://www.astroclub.kiev.ua/forum/ind ... ic=46758.0
Telescope: TS 152/900/Bresser 102/1350
Baader D-ERF 160MM
2xBaader 1.25 GPC
2xLunt 50mm
Lunt Cak B1200
Coronado BF15
Camera: Apollo Max 432M/ Apollo Mini 429M/Player One Mars II 462M/QHY 290MM
Mounh: 2xSky Watcher AZEQ6
Telecentric Lense: Televue Powermate 2/2.5x/4X/5X
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Re: Double Stack Lunt CaK filter
My scope is pretty well corrected at 393 even at 102mm but my seeing rarely allows imaging in Cak at 102mm. Cak at 102mm is equivalent to approx 170mm in Ha ((656/393)*102mm). I am close to critically sampled when the scope is masked to 60 with the zwo 290 (80mm mask is the best if seeing allows).OlegLviv wrote: ↑Fri Jan 28, 2022 11:13 amWhy you masked to 60mm? Because CAK love f20?torsinadoc wrote: ↑Fri Jan 28, 2022 9:02 am102 f11 achromat masked to 60. If seeing allows I can get good results at full aperture. I use a zwo 1600 for FD and zwo 290 for close ups.
https://brierleyhillsolar.blogspot.com/ ... pling.html
Here is an interesting thread
viewtopic.php?t=25115
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Re: Double Stack Lunt CaK filter
Thank you for answer and interesting link!
In my mind ERF for 100 mm refractor CAK do not need?
Why do you decided buy Lunt but not Quark?
In my mind ERF for 100 mm refractor CAK do not need?
Why do you decided buy Lunt but not Quark?
https://www.facebook.com/oleg.lavigne/
https://www.astrobin.com/users/RamonLviv/
https://www.astroclub.kiev.ua/forum/ind ... ic=46758.0
Telescope: TS 152/900/Bresser 102/1350
Baader D-ERF 160MM
2xBaader 1.25 GPC
2xLunt 50mm
Lunt Cak B1200
Coronado BF15
Camera: Apollo Max 432M/ Apollo Mini 429M/Player One Mars II 462M/QHY 290MM
Mounh: 2xSky Watcher AZEQ6
Telecentric Lense: Televue Powermate 2/2.5x/4X/5X
https://www.astrobin.com/users/RamonLviv/
https://www.astroclub.kiev.ua/forum/ind ... ic=46758.0
Telescope: TS 152/900/Bresser 102/1350
Baader D-ERF 160MM
2xBaader 1.25 GPC
2xLunt 50mm
Lunt Cak B1200
Coronado BF15
Camera: Apollo Max 432M/ Apollo Mini 429M/Player One Mars II 462M/QHY 290MM
Mounh: 2xSky Watcher AZEQ6
Telecentric Lense: Televue Powermate 2/2.5x/4X/5X
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Re: Double Stack Lunt CaK filter
I use an ERF above 100mm. I have only had seeing twice to support it. I had prior negative experience with a daystar quark and decided to stick with the Lunt.
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Re: Double Stack Lunt CaK filter
Oleg,
The Quark offering is a CaH filter, not CaK and is 5A bandwidth - double that of the Lunt.
https://www.teleskop-express.de/shop/pr ... ilter.html
The Quark offering is a CaH filter, not CaK and is 5A bandwidth - double that of the Lunt.
https://www.teleskop-express.de/shop/pr ... ilter.html
"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: Double Stack Lunt CaK filter
I understand you because had Quark chromosphere and had PST mod1 and PST better more contrast+you can put differents barlowtorsinadoc wrote: ↑Fri Jan 28, 2022 8:53 pmI use an ERF above 100mm. I have only had seeing twice to support it. I had prior negative experience with a daystar quark and decided to stick with the Lunt.
You say above 100mm for CAK ERF, or you mean for HA?
https://www.facebook.com/oleg.lavigne/
https://www.astrobin.com/users/RamonLviv/
https://www.astroclub.kiev.ua/forum/ind ... ic=46758.0
Telescope: TS 152/900/Bresser 102/1350
Baader D-ERF 160MM
2xBaader 1.25 GPC
2xLunt 50mm
Lunt Cak B1200
Coronado BF15
Camera: Apollo Max 432M/ Apollo Mini 429M/Player One Mars II 462M/QHY 290MM
Mounh: 2xSky Watcher AZEQ6
Telecentric Lense: Televue Powermate 2/2.5x/4X/5X
https://www.astrobin.com/users/RamonLviv/
https://www.astroclub.kiev.ua/forum/ind ... ic=46758.0
Telescope: TS 152/900/Bresser 102/1350
Baader D-ERF 160MM
2xBaader 1.25 GPC
2xLunt 50mm
Lunt Cak B1200
Coronado BF15
Camera: Apollo Max 432M/ Apollo Mini 429M/Player One Mars II 462M/QHY 290MM
Mounh: 2xSky Watcher AZEQ6
Telecentric Lense: Televue Powermate 2/2.5x/4X/5X
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Re: Double Stack Lunt CaK filter
For 100mm ERF CaK you just need to use a uv/ir filter that passes Ca mounted high on the snout of the filter assembly in the focuser.
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Re: Double Stack Lunt CaK filter
I use a 2" Baader Blue CCD filter (https://www.baader-planetarium.com/en/b ... blue).html ) with a 2" Astronomik L1 UV-IR filter as a ERF on the DIY CaK filter setup.
Can we get back on track and limit this discussion to Lunt filters and double stacking.
Thanks
Can we get back on track and limit this discussion to Lunt filters and double stacking.
Thanks
"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
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"Imaging Sunlight - using a digital spectroheliograph" - Springer
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Re: Double Stack Lunt CaK filter
Seeing was terrible. I had to use the Apollo M Max (imx 432)+ 102 F11 (masked to 60). I am under sampled but here are some images.
First thing I noticed when I tried to push the settings for the prom was a reflection (double image?) that obscured some of the proms. I added a quick tilt adjuster between the two modules and adjusted it to push is off (I will try and 3d print a solution. As an aside, i really like this camera. The data is so clean
scope: Canadian Telescope 102/1100 fraunhofer achromat masked to 60
Camera: Apollo M Max (imx 432)
Sharp Cap pro
AS3! 40/1000 images
Unprocessed image
unprocessed Calcium Prom by Torsinadoc, on Flickr
Camera Settings
[Apollo-M MAX (IMX432)]
FrameType=Light
Binning=1
Colour Space=MONO8
Capture Area=1608x1104
Output Format=SER file (*.ser)(Auto)
Pan=0
Pan=0
Flip=None
Temperature=25.7999992370605
USB Speed=100
Offset=80
Frame Rate Limit=Maximum
Analogue Gain=314
Exposure=10.0000ms
Timestamp Frames=Off
Background Subtraction=Off
Planet/Disk Stabilization=Off
Banding Threshold=35
Banding Suppression=0
Apply Flat=None
Subtract Dark=None
Display Black Point=0
Display MidTone Point=0.5
Display White Point=1
Notes=
TimeStamp=2022-01-29T17:39:30.4046869Z
SharpCapVersion=4.0.8604.0
StartCapture=2022-01-29T17:39:30.3975598Z
MidCapture=2022-01-29T17:39:32.1305598Z
EndCapture=2022-01-29T17:39:33.8643555Z
Duration=3.467s
FrameCount=344
TimeZone=-6.00
First thing I noticed when I tried to push the settings for the prom was a reflection (double image?) that obscured some of the proms. I added a quick tilt adjuster between the two modules and adjusted it to push is off (I will try and 3d print a solution. As an aside, i really like this camera. The data is so clean
scope: Canadian Telescope 102/1100 fraunhofer achromat masked to 60
Camera: Apollo M Max (imx 432)
Sharp Cap pro
AS3! 40/1000 images
Unprocessed image
unprocessed Calcium Prom by Torsinadoc, on Flickr
Camera Settings
[Apollo-M MAX (IMX432)]
FrameType=Light
Binning=1
Colour Space=MONO8
Capture Area=1608x1104
Output Format=SER file (*.ser)(Auto)
Pan=0
Pan=0
Flip=None
Temperature=25.7999992370605
USB Speed=100
Offset=80
Frame Rate Limit=Maximum
Analogue Gain=314
Exposure=10.0000ms
Timestamp Frames=Off
Background Subtraction=Off
Planet/Disk Stabilization=Off
Banding Threshold=35
Banding Suppression=0
Apply Flat=None
Subtract Dark=None
Display Black Point=0
Display MidTone Point=0.5
Display White Point=1
Notes=
TimeStamp=2022-01-29T17:39:30.4046869Z
SharpCapVersion=4.0.8604.0
StartCapture=2022-01-29T17:39:30.3975598Z
MidCapture=2022-01-29T17:39:32.1305598Z
EndCapture=2022-01-29T17:39:33.8643555Z
Duration=3.467s
FrameCount=344
TimeZone=-6.00
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Re: Double Stack Lunt CaK filter
Thanks for that.
The image was then a stack of 40 x 10ms exposures =0.4 sec? gain=314
(The log file only shows 344 frames???)
The image was then a stack of 40 x 10ms exposures =0.4 sec? gain=314
(The log file only shows 344 frames???)
"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: Double Stack Lunt CaK filter
That is correct. The videos were exposure 10 ms and gain of 318. I took eight separate videos. Some were longer than others. They all had the same camera settings but the duration was shorter on a few. This image was stacked with the above settings
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Re: Double Stack Lunt CaK filter
Nice camera!
Last edited by OlegLviv on Tue Feb 01, 2022 12:19 pm, edited 1 time in total.
https://www.facebook.com/oleg.lavigne/
https://www.astrobin.com/users/RamonLviv/
https://www.astroclub.kiev.ua/forum/ind ... ic=46758.0
Telescope: TS 152/900/Bresser 102/1350
Baader D-ERF 160MM
2xBaader 1.25 GPC
2xLunt 50mm
Lunt Cak B1200
Coronado BF15
Camera: Apollo Max 432M/ Apollo Mini 429M/Player One Mars II 462M/QHY 290MM
Mounh: 2xSky Watcher AZEQ6
Telecentric Lense: Televue Powermate 2/2.5x/4X/5X
https://www.astrobin.com/users/RamonLviv/
https://www.astroclub.kiev.ua/forum/ind ... ic=46758.0
Telescope: TS 152/900/Bresser 102/1350
Baader D-ERF 160MM
2xBaader 1.25 GPC
2xLunt 50mm
Lunt Cak B1200
Coronado BF15
Camera: Apollo Max 432M/ Apollo Mini 429M/Player One Mars II 462M/QHY 290MM
Mounh: 2xSky Watcher AZEQ6
Telecentric Lense: Televue Powermate 2/2.5x/4X/5X
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