Feedback requested from Lunt/ Quark CaK/H users
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Feedback requested from Lunt/ Quark CaK/H users
I'm trying to determine the key factors in being able to image CaK proms with the Lunt CaK/ Quark CaH filter.
I have received some data already but would like to extend the data as far as possible.
If you've had success/ failure to image CaK proms please let me know. I'll share the outcome results. Thanks.
Typical data required:
Observers name
Effective aperture
Effective focal length
Camera
Gain setting
Pixel size
Exposure
Stack size
Sample image - if possible.
Drop me an email: kenm(dot)harrison(at)gmail(dot)com
I have received some data already but would like to extend the data as far as possible.
If you've had success/ failure to image CaK proms please let me know. I'll share the outcome results. Thanks.
Typical data required:
Observers name
Effective aperture
Effective focal length
Camera
Gain setting
Pixel size
Exposure
Stack size
Sample image - if possible.
Drop me an email: kenm(dot)harrison(at)gmail(dot)com
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Re: Feedback requested from Lunt/ Quark CaK/H users
Total failure so far Ken with a:
CaK PST
Lunt B1800 wedge + 100mm stopped TEC140 + PGR Grasshopper 3 and ASI174 with numerous gain and gamma - nothing
Alexandra
CaK PST
Lunt B1800 wedge + 100mm stopped TEC140 + PGR Grasshopper 3 and ASI174 with numerous gain and gamma - nothing
Alexandra
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Re: Feedback requested from Lunt/ Quark CaK/H users
Lunt CaK BF1200/Orion ED80T CF/ASI174MM or Skyris 236M with Gamma cranked up I can catch a very faint image but unable to stack due to lack of any real detail. Will probably try some longer exposures when there is a significant prom present.
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Re: Feedback requested from Lunt/ Quark CaK/H users
Hi Ken: I will try one of the next sessions.
Franco
Franco
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Re: Feedback requested from Lunt/ Quark CaK/H users
My homebrew CaK filter - proms easy. I think (excessive) out of band blocking is key.
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Re: Feedback requested from Lunt/ Quark CaK/H users
I'll send more data notes from today Ken. I'll email you them tomorrow. Lovely prom's in CaK today using my unmodified Lunt b1800 CaK module and Bresser 100mm Aromatic stopped to 80mm.
10ft x 6ft Solar RoR with Warm Room
Lunt 60mm Double Stack HA
80ed WL+ Lunt Hershal Wedge + Badder K-Line filter.
100mm AR + Lunt b1800 Ca-K module.
Neq6 Eq Mount.
2.7m Pulsar Dome.
11in Celestron SCT + White Light Filter.
70mm AR Stellavue.
12inch OO Newtonian.
Eq8 r Pro Mount.
Lunt 60mm Double Stack HA
80ed WL+ Lunt Hershal Wedge + Badder K-Line filter.
100mm AR + Lunt b1800 Ca-K module.
Neq6 Eq Mount.
2.7m Pulsar Dome.
11in Celestron SCT + White Light Filter.
70mm AR Stellavue.
12inch OO Newtonian.
Eq8 r Pro Mount.
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Re: Feedback requested from Lunt/ Quark CaK/H users
My Lunt CaK module arrived a bit late for my solar season last summer in 2021, so I did not get too many test attempts. I was able to find out a few prominences from my data, different days.
Lunt 12 CaK, TS 102mm f/11, ZWO ASI174MM.
Lunt 12 CaK, TS 102mm f/11, ZWO ASI174MM.
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Re: Feedback requested from Lunt/ Quark CaK/H users
if you are using a lower end camera or an 8-bit camera, it is not possible.
Here is some raw video using a PGR Grasshopper of what I believe is the largest prominence ever imaged from the Earth’s surface that I got at a sci-fi festival in Atlanta. It extended out to over 1.2 million miles before fading away.
The video starts in h-alpha and around 30 secs switches over to CaK. It gets really interesting around 1:44.
It’s rough video and passing clouds but you can see the high exposure and low gamma.
https://youtu.be/RoiYAYEDgzQ
the finished image:
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Stephen W. Ramsden
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Re: Feedback requested from Lunt/ Quark CaK/H users
Stephen,
That certainly is among the largest prominences I have seen images of. I think it certainly IS the tallest! I wonder how much of it could have been seen visually?
Is the video and CaK image yours?
James
That certainly is among the largest prominences I have seen images of. I think it certainly IS the tallest! I wonder how much of it could have been seen visually?
Is the video and CaK image yours?
James
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Re: Feedback requested from Lunt/ Quark CaK/H users
Stephen,
Very good mate!
Can you confirm the camera - Grasshopper seems to cover many - Express, IMX174, IMX252??
What typical settings - exposure , gain?
Did you stack images for the final ????
This would help others understand the challenge.
Thanks.
Very good mate!
Can you confirm the camera - Grasshopper seems to cover many - Express, IMX174, IMX252??
What typical settings - exposure , gain?
Did you stack images for the final ????
This would help others understand the challenge.
Thanks.
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Re: Feedback requested from Lunt/ Quark CaK/H users
Hi Ken,
I can get pictures of Ca K prominences with 0.26 nm or 0.38 nm FWHM filters. Any sensor will do. It is mainly a matter of using long exposure time since the prominences are much fainter in Ca K (or Ca H) compared to Ha.
As said by Mark, cutting unwanting bandpass might probably help.
This one was taken with a double stack 0.26 nm + 0.38 nm FWHM. There is nothing spectacular there. But it provides a feeling of the difference of brightness between the solar disk and the prominences in Ca K :
http://astrosurf.com/viladrich/astro/so ... 00-ddp.jpg
BTW, fantastic video Stephen !!
I can get pictures of Ca K prominences with 0.26 nm or 0.38 nm FWHM filters. Any sensor will do. It is mainly a matter of using long exposure time since the prominences are much fainter in Ca K (or Ca H) compared to Ha.
As said by Mark, cutting unwanting bandpass might probably help.
This one was taken with a double stack 0.26 nm + 0.38 nm FWHM. There is nothing spectacular there. But it provides a feeling of the difference of brightness between the solar disk and the prominences in Ca K :
http://astrosurf.com/viladrich/astro/so ... 00-ddp.jpg
BTW, fantastic video Stephen !!
Christian Viladrich
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Re: Feedback requested from Lunt/ Quark CaK/H users
Christian,
Not only did you pick the prominences up you easily got the spicule layer on the limb too!!
James
Not only did you pick the prominences up you easily got the spicule layer on the limb too!!
James
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Re: Feedback requested from Lunt/ Quark CaK/H users
My homebrew CaK filter - proms easy. I think (excessive) out of band blocking is key.
Like Mark and Christian I used a DIY CaK module for the images that follow. Since they are not intended for visual use, they probably offer much greater through-put than the standard CaK PST or Lunt CaK module. It consisted of a 2 inch Baader Blue CCD filter acting as a sub-diameter ERF, a Baader K-line filter acting as a pre-blocking filter, and the the CaK PST yellow dichroic filter for the narrow 2.2 A element. While fainter than H alpha prominences, CaK proms seem bright enough to capture without too much difficulty. Here's a hodge-podge of images from Cycle 24:I can get pictures of Ca K prominences with 0.26 nm or 0.38 nm FWHM filters. Any sensor will do. It is mainly a matter of using long exposure time since the prominences are much fainter in Ca K (or Ca H) compared to Ha.
I usually avoid overexposing with CaK runs with exposures between 0.057 ms to 0.385 ms and use minimal gain (160) and gamma (1000), preferring to bring out detail in post-stacking processing. I capture 8-bit avi files. I usually run captures for 20 sec and get about 300 frames, and stack the best 10-20%. All images were obtained using a Synta ED100/900 (f9) and a cooled PGR Chameleon @ 18 fps (Sony ICX445 CCD - 1296 x 964 with 3.75μm x 3.75μm pixels). As I recall the last image used a 2X TeleVue Big Barlow.
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Re: Feedback requested from Lunt/ Quark CaK/H users
Bob,
Your DIY CaK filter does very well on prominences. Among the best I have seen! I would think they would optimize commercial CaK filters for imaging and not visual because most people cannot see CaK very well. It may be a safety issue since a filter rated for visual may block more harmful radiation than one intended for imaging only. My guess...
James
Your DIY CaK filter does very well on prominences. Among the best I have seen! I would think they would optimize commercial CaK filters for imaging and not visual because most people cannot see CaK very well. It may be a safety issue since a filter rated for visual may block more harmful radiation than one intended for imaging only. My guess...
James
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Re: Feedback requested from Lunt/ Quark CaK/H users
Hi James,
From what I know the commercial CaK filters incorporate an IR blocking ITF and other filtering, and likely a hefty amount of dimming at 394 nm. I know for sure that my DIY CaK module lets a lot of VIS and IR energy through to the downstream filters, and would be totally unsafe for visual use due to no IR blocking beyond ~ 1100 nm where the Baader B CCD filter transmission turns back on. Now working on adding a KG3 and better pre-filtering in tilted filter cells for double and perhaps triple stacked tuning and reflection suppression.
The OEM's are confronted with a dilemma with CaK being a very small segment of a narrow market to begin with, and making an even more rarefied product just for imaging might be too much trouble considering they already advise it's generally an imaging filter to begin with due to the most peoples eye's lack of sensitivity at 394 nm. Added to this is the fact that it's technically UV, and the very real chance some moron would look through it despite any warnings, setting them up for an expensive lawsuit even though they would win in the end from a negligent user.
From what I know the commercial CaK filters incorporate an IR blocking ITF and other filtering, and likely a hefty amount of dimming at 394 nm. I know for sure that my DIY CaK module lets a lot of VIS and IR energy through to the downstream filters, and would be totally unsafe for visual use due to no IR blocking beyond ~ 1100 nm where the Baader B CCD filter transmission turns back on. Now working on adding a KG3 and better pre-filtering in tilted filter cells for double and perhaps triple stacked tuning and reflection suppression.
The OEM's are confronted with a dilemma with CaK being a very small segment of a narrow market to begin with, and making an even more rarefied product just for imaging might be too much trouble considering they already advise it's generally an imaging filter to begin with due to the most peoples eye's lack of sensitivity at 394 nm. Added to this is the fact that it's technically UV, and the very real chance some moron would look through it despite any warnings, setting them up for an expensive lawsuit even though they would win in the end from a negligent user.
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Re: Feedback requested from Lunt/ Quark CaK/H users
Bob,
Being ignorant of the workings of filter tech I am trying to understand this. If an ultra narrowband filter, CaK in this case 394nm, should let only a narrow passband of the light through at that wavelength, right? Why is IR such a problem? By nature why would it pass it at all? 1100nm is far removed from the 393nm line the filter is supposed to be isolating. I thought maybe an ITF filter may be used to keep the narrowband filters cool and from damage. I always thought and ultra narrowband passed ONLY the designed spectral frequency and nothing else. Am I wrong or too strict in my understanding of it?
Thanks
James.
P.S. Or is the ITF there to block off bandwidth light that bleeds through the filter. Overwhelms it?
Being ignorant of the workings of filter tech I am trying to understand this. If an ultra narrowband filter, CaK in this case 394nm, should let only a narrow passband of the light through at that wavelength, right? Why is IR such a problem? By nature why would it pass it at all? 1100nm is far removed from the 393nm line the filter is supposed to be isolating. I thought maybe an ITF filter may be used to keep the narrowband filters cool and from damage. I always thought and ultra narrowband passed ONLY the designed spectral frequency and nothing else. Am I wrong or too strict in my understanding of it?
Thanks
James.
P.S. Or is the ITF there to block off bandwidth light that bleeds through the filter. Overwhelms it?
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Re: Feedback requested from Lunt/ Quark CaK/H users
Hi James,
All narrowband filters we generally encounter are actually a filter system. CaK is no different than H alpha in this regard. You want to generally block all out-of-band transmission to OD 5 for safe visual use from about 250 nm out to 2500 nm, and I'm aware of no single filter that can do this, let alone be a narrow-band filter.
Additionally, we want to avoid excessive heating of the filers themselves to maintain the proper band-pass (heat red-shifts most dielectric coated interference filters) and prolong the life of the downstream filters - especially if they are soft-coated on soda-lime glass substrates. Even H alpha etalons will pass a significant amount of out-of-band wavelengths and energy that needs a great deal of additional filtering.
Lunt H alpha etalon. NOTE: Transmission shown with RG630 and IR blocked ERF in place.
So we generally will have an ERF filter that will block UV below about 400 nm (and with an RG630, anything below about 600 nm), and IR from about 700 to 1200 nm. Then you usually employ a KG3. BG38, or ITF to block IR out to 3000 nm or so. Along with these there are also "conditioning filter(s)" such as the 6-10 A blocking "order selection" filter which isolates the H alpha etalon peak from the side-band harmonic peaks, and it might be used on an additional substrate to further adjust image brightness to a comfortable level.
For CaK, using a Baader Blue CCD filter does do some UV and IR blocking, but it lets everything from slightly below 400 nm to about 500 nm through unimpeded. This is where a tremendous amount of the Sun's energy output lies, and can greatly heat the subsequent filter(s), in addition to letting everything above about 1200 nm pass.
We can then use another filter such as the Baader K line as a conditioning filter to really narrow the transmission for the PST or similar filter - but it too will have a lot of transmission in the near to mid IR.
Other conditioning filters could be substituted for the K-line, such as some long and short-pass filters, a Fluorescence filter centered at 390 nm, etc.
Finally the yellow dichroic filter used as the narrow-band blocking filter for CaK also has out-of-band-transmission from VIS into the IR.
The IR passed by all these filters is where using a KG3 or similar filter would come into play. Even if your camera sensor cannot "see" beyond 1100 nm or so, longer IR from the Sun may negatively affect it with increased electronic temperatures and noise, and why I decided to cool my PGR Chameleon - after all we're generally using them in higher daytime temperatures to begin with, and they can and do get hot even when not pointed at the Sun. My engineering philosophy is to try to mitigate all possible issues so that they do not add up cumulatively to deteriorate performance. It's sort of like shedding every possible gram of extra weight a professional race car design team engages in to enhance performance...
All narrowband filters we generally encounter are actually a filter system. CaK is no different than H alpha in this regard. You want to generally block all out-of-band transmission to OD 5 for safe visual use from about 250 nm out to 2500 nm, and I'm aware of no single filter that can do this, let alone be a narrow-band filter.
Additionally, we want to avoid excessive heating of the filers themselves to maintain the proper band-pass (heat red-shifts most dielectric coated interference filters) and prolong the life of the downstream filters - especially if they are soft-coated on soda-lime glass substrates. Even H alpha etalons will pass a significant amount of out-of-band wavelengths and energy that needs a great deal of additional filtering.
Lunt H alpha etalon. NOTE: Transmission shown with RG630 and IR blocked ERF in place.
So we generally will have an ERF filter that will block UV below about 400 nm (and with an RG630, anything below about 600 nm), and IR from about 700 to 1200 nm. Then you usually employ a KG3. BG38, or ITF to block IR out to 3000 nm or so. Along with these there are also "conditioning filter(s)" such as the 6-10 A blocking "order selection" filter which isolates the H alpha etalon peak from the side-band harmonic peaks, and it might be used on an additional substrate to further adjust image brightness to a comfortable level.
For CaK, using a Baader Blue CCD filter does do some UV and IR blocking, but it lets everything from slightly below 400 nm to about 500 nm through unimpeded. This is where a tremendous amount of the Sun's energy output lies, and can greatly heat the subsequent filter(s), in addition to letting everything above about 1200 nm pass.
We can then use another filter such as the Baader K line as a conditioning filter to really narrow the transmission for the PST or similar filter - but it too will have a lot of transmission in the near to mid IR.
Other conditioning filters could be substituted for the K-line, such as some long and short-pass filters, a Fluorescence filter centered at 390 nm, etc.
Finally the yellow dichroic filter used as the narrow-band blocking filter for CaK also has out-of-band-transmission from VIS into the IR.
The IR passed by all these filters is where using a KG3 or similar filter would come into play. Even if your camera sensor cannot "see" beyond 1100 nm or so, longer IR from the Sun may negatively affect it with increased electronic temperatures and noise, and why I decided to cool my PGR Chameleon - after all we're generally using them in higher daytime temperatures to begin with, and they can and do get hot even when not pointed at the Sun. My engineering philosophy is to try to mitigate all possible issues so that they do not add up cumulatively to deteriorate performance. It's sort of like shedding every possible gram of extra weight a professional race car design team engages in to enhance performance...
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Goldendale Observatory
Curiosity is the father of knowledge; uncertainty is the mother of wisdom.
Dark-Sky Defenders
Goldendale Observatory
- DeepSolar64
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Re: Feedback requested from Lunt/ Quark CaK/H users
Thank you for the very detailed explanation, Bob. I knew some filters are a system, like the Ha filter system on my Coronados. ERF, stacking etalon, main etalon and the blocking filter. And white light uses either a dark NDF as a main filter or a Herschel wedge with an NDF and polarizer and then if one chooses a 430, 540, K-line filter etc. I was thinking a bit to simple I guess. In solar no one uses a single filter element to observe the sun unless it's an over the aperture filter for white light observing but that's not narrow band unless used with another filter. Now how well do white light filters actually do at blocking IR and UV radiation?
James
James
Lunt 8x32 SUNoculars
Orion 70mm Solar Telescope
Celestron AstroMaster Alt/Az Mount
Meade Coronado SolarMax II 60 DS
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Astro-Tech AT72EDII with Altair solar wedge
Celestron NexStar 102GT with Altair solar wedge
Losmandy AZ8 Alt/Az Mount
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Cameras: ZWO ASI178MM, PGR Grasshopper, PGR Flea
Lunt, Coronado, TeleVue, Orion and Meade eyepieces
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Orion 70mm Solar Telescope
Celestron AstroMaster Alt/Az Mount
Meade Coronado SolarMax II 60 DS
Meade Coronado SolarMax II 90 DS
Meade Coronado AZS Alt/Az Mount
Astro-Tech AT72EDII with Altair solar wedge
Celestron NexStar 102GT with Altair solar wedge
Losmandy AZ8 Alt/Az Mount
Sky-Watcher AZGTI Alt-Az GoTo mount
Cameras: ZWO ASI178MM, PGR Grasshopper, PGR Flea
Lunt, Coronado, TeleVue, Orion and Meade eyepieces
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- Bob Yoesle
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Re: Feedback requested from Lunt/ Quark CaK/H users
You can find some good filter curves here, and for the Baader AstroSolar 5 film, a little extra UV (and IR to a lesser degree) suppression wouldn't hurt.
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
- DeepSolar64
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Re: Feedback requested from Lunt/ Quark CaK/H users
Thanks for the data, Bob. I think I have diverted this conversation a bit off topic. I'll let it get back on to CaK-H Lunt/Quark user feedback.
Lunt 8x32 SUNoculars
Orion 70mm Solar Telescope
Celestron AstroMaster Alt/Az Mount
Meade Coronado SolarMax II 60 DS
Meade Coronado SolarMax II 90 DS
Meade Coronado AZS Alt/Az Mount
Astro-Tech AT72EDII with Altair solar wedge
Celestron NexStar 102GT with Altair solar wedge
Losmandy AZ8 Alt/Az Mount
Sky-Watcher AZGTI Alt-Az GoTo mount
Cameras: ZWO ASI178MM, PGR Grasshopper, PGR Flea
Lunt, Coronado, TeleVue, Orion and Meade eyepieces
Visual Observer
" Way more fun to see it! "
Orion 70mm Solar Telescope
Celestron AstroMaster Alt/Az Mount
Meade Coronado SolarMax II 60 DS
Meade Coronado SolarMax II 90 DS
Meade Coronado AZS Alt/Az Mount
Astro-Tech AT72EDII with Altair solar wedge
Celestron NexStar 102GT with Altair solar wedge
Losmandy AZ8 Alt/Az Mount
Sky-Watcher AZGTI Alt-Az GoTo mount
Cameras: ZWO ASI178MM, PGR Grasshopper, PGR Flea
Lunt, Coronado, TeleVue, Orion and Meade eyepieces
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- Merlin66
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Re: Feedback requested from Lunt/ Quark CaK/H users
Bob, James, et al,
Very interesting discussions on non standard Lunt issues.
I’d like to keep the topic on track to provide some useful data to Lunt users who wish to record the CaK proms.
I thank everyone for their contribution so far.
I haven’t received any positive response from Quark users……
Very interesting discussions on non standard Lunt issues.
I’d like to keep the topic on track to provide some useful data to Lunt users who wish to record the CaK proms.
I thank everyone for their contribution so far.
I haven’t received any positive response from Quark users……
"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
- DeepSolar64
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Re: Feedback requested from Lunt/ Quark CaK/H users
Good luck Ken. I just wish I had a CaH or CaK module to give input on. Good luck.
Lunt 8x32 SUNoculars
Orion 70mm Solar Telescope
Celestron AstroMaster Alt/Az Mount
Meade Coronado SolarMax II 60 DS
Meade Coronado SolarMax II 90 DS
Meade Coronado AZS Alt/Az Mount
Astro-Tech AT72EDII with Altair solar wedge
Celestron NexStar 102GT with Altair solar wedge
Losmandy AZ8 Alt/Az Mount
Sky-Watcher AZGTI Alt-Az GoTo mount
Cameras: ZWO ASI178MM, PGR Grasshopper, PGR Flea
Lunt, Coronado, TeleVue, Orion and Meade eyepieces
Visual Observer
" Way more fun to see it! "
Orion 70mm Solar Telescope
Celestron AstroMaster Alt/Az Mount
Meade Coronado SolarMax II 60 DS
Meade Coronado SolarMax II 90 DS
Meade Coronado AZS Alt/Az Mount
Astro-Tech AT72EDII with Altair solar wedge
Celestron NexStar 102GT with Altair solar wedge
Losmandy AZ8 Alt/Az Mount
Sky-Watcher AZGTI Alt-Az GoTo mount
Cameras: ZWO ASI178MM, PGR Grasshopper, PGR Flea
Lunt, Coronado, TeleVue, Orion and Meade eyepieces
Visual Observer
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- ffellah
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Re: Feedback requested from Lunt/ Quark CaK/H users
Hi Ken: this image is from yesterday. My first try at this in CaH. The scope was the Evostar 72mm stopped down to 35mm. Original focal length is 420mm. The camera is PG ICX814 CCD chip, pixel size is 3.69. I stacked 95 of 100 frames. The rest should be here:
Franco
Camera=Grasshopper3 GS3-U3-91S6M
Filter=R
Profile=Sun
Filename=Sun_115217.ser
Date=230122
Start=115212.293
Mid=115217.844
End=115223.396
Start(UT)=165212.293
Mid(UT)=165217.844
End(UT)=165223.396
Duration=11.103s
Date_format=ddMMyy
Time_format=HHmmss
LT=UT -5h
Frames captured=100
File type=SER
Binning=no
ROI=3376x2704
ROI(Offset)=0x0
FPS (avg.)=9
Shutter=3.797ms
Gain=2121 (88%)
AutoHisto=75 (off)
Brightness=0 (off)
Exposure=512
AutoExposure=off
FPS=10.0 (off)
Sharpness=1431 (off)
Mode7=off
SoftwareGain=10 (off)
Gamma=687 (off)
Histogramm(min)=0
Histogramm(max)=255
Histogramm=100%
Noise(avg.deviation)=n/a
Limit=100 Frames
Sensor temperature=26.2°C
Franco
Camera=Grasshopper3 GS3-U3-91S6M
Filter=R
Profile=Sun
Filename=Sun_115217.ser
Date=230122
Start=115212.293
Mid=115217.844
End=115223.396
Start(UT)=165212.293
Mid(UT)=165217.844
End(UT)=165223.396
Duration=11.103s
Date_format=ddMMyy
Time_format=HHmmss
LT=UT -5h
Frames captured=100
File type=SER
Binning=no
ROI=3376x2704
ROI(Offset)=0x0
FPS (avg.)=9
Shutter=3.797ms
Gain=2121 (88%)
AutoHisto=75 (off)
Brightness=0 (off)
Exposure=512
AutoExposure=off
FPS=10.0 (off)
Sharpness=1431 (off)
Mode7=off
SoftwareGain=10 (off)
Gamma=687 (off)
Histogramm(min)=0
Histogramm(max)=255
Histogramm=100%
Noise(avg.deviation)=n/a
Limit=100 Frames
Sensor temperature=26.2°C
- Attachments
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- 115217 CaH proms.jpg (603.72 KiB) Viewed 689 times
- Merlin66
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Re: Feedback requested from Lunt/ Quark CaK/H users
Franco,
Thanks for that! Never seen a CaH prom before....
I assume this was a DayStar CaH Quark?
What acquisition software?
A little surprised to see gain=2121
Thanks for that! Never seen a CaH prom before....
I assume this was a DayStar CaH Quark?
What acquisition software?
A little surprised to see gain=2121
"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
- DeepSolar64
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Re: Feedback requested from Lunt/ Quark CaK/H users
Absolutely beautiful CaH proms Franco!
Lunt 8x32 SUNoculars
Orion 70mm Solar Telescope
Celestron AstroMaster Alt/Az Mount
Meade Coronado SolarMax II 60 DS
Meade Coronado SolarMax II 90 DS
Meade Coronado AZS Alt/Az Mount
Astro-Tech AT72EDII with Altair solar wedge
Celestron NexStar 102GT with Altair solar wedge
Losmandy AZ8 Alt/Az Mount
Sky-Watcher AZGTI Alt-Az GoTo mount
Cameras: ZWO ASI178MM, PGR Grasshopper, PGR Flea
Lunt, Coronado, TeleVue, Orion and Meade eyepieces
Visual Observer
" Way more fun to see it! "
Orion 70mm Solar Telescope
Celestron AstroMaster Alt/Az Mount
Meade Coronado SolarMax II 60 DS
Meade Coronado SolarMax II 90 DS
Meade Coronado AZS Alt/Az Mount
Astro-Tech AT72EDII with Altair solar wedge
Celestron NexStar 102GT with Altair solar wedge
Losmandy AZ8 Alt/Az Mount
Sky-Watcher AZGTI Alt-Az GoTo mount
Cameras: ZWO ASI178MM, PGR Grasshopper, PGR Flea
Lunt, Coronado, TeleVue, Orion and Meade eyepieces
Visual Observer
" Way more fun to see it! "
- ffellah
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Re: Feedback requested from Lunt/ Quark CaK/H users
Ken: yes, a Quark CAH, Firecapture 2.6 (?) software. As I said, this is something I never tried before, so I am a bit surprised too the gain was so high. I will try different things next time to see where the threshold is with gain and exposure before you can see the proms. Also surprised by the fact that I needed such high gain, as the 814 chip is very sensitive: the proms at this line must be very faint.
Franco
Franco
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Re: Feedback requested from Lunt/ Quark CaK/H users
When the gain is so high the number of 'bits' of available dynamic range a camera has is reduced, so, the many faint shades of grey in a Ca prom is compressed into a smaller dynamic range may well make it easier to record. Eric achieves a similar thing with his CaK prom shots by reducing the gamma - again doing this reduces the dynamic range capability of a camera chip.ffellah wrote: ↑Tue Jan 25, 2022 11:37 am Ken: yes, a Quark CAH, Firecapture 2.6 (?) software. As I said, this is something I never tried before, so I am a bit surprised too the gain was so high. I will try different things next time to see where the threshold is with gain and exposure before you can see the proms. Also surprised by the fact that I needed such high gain, as the 814 chip is very sensitive: the proms at this line must be very faint.
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!