Different Ca-K options, differences?

Use this section to discuss "standard" Baader/Coronado/ Lunt SolarView/ Daystar, etc… filters, cameras and scopes. No mods, just questions/ answers and reviews.
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Bob Yoesle
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Re: Different Ca-K options, differences?

Post by Bob Yoesle » Fri Jul 07, 2017 5:38 am

Just to ad my 2 cents worth, the relatively inexpensive (especially used) Synta 100ED f/9 scopes (Celestron, Skywatcher, etc.) don't do too bad at 394 nm either:
CaK hi res.jpg
CaK hi res.jpg (497.46 KiB) Viewed 1276 times
Equivalent to a 160 mm scope at H alpha BTW... Orion ED 100 f/9, 2x TeleVue Big Barlow, DS CaK home brew, PGR Chameleon.
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Re: Different Ca-K options, differences?

Post by MalVeauX » Mon Aug 20, 2018 8:25 pm

Bob Yoesle wrote:
Fri Jul 07, 2017 5:38 am
DS CaK home brew
Hey Bob,

Do you mind expanding on this double stack CaK home brew setup? I'm really starting to feel like getting into a double stack calcium system with my 6 inch refractor since the resolution would be significantly higher than an HA system and I just really like the look of calcium.

Does your system allow you to see filaments and prominences in Calcium?

I'm curious of course what your system is and how you stacked it and how you manage the thermal energy?

Thanks!

Very best,

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Re: Different Ca-K options, differences?

Post by Bob Yoesle » Tue Aug 21, 2018 3:30 pm

See related post How to DS CaK
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Re: Different Ca-K options, differences?

Post by george9 » Fri Aug 24, 2018 3:53 am

Why is the Lunt CaK stated as only for refractors and the Quark for both reflectors and refractors?

I had the Quark CaH and I could tell there was a lot of out-of-band light. My eye could see a bright blue sun with no CaH detail (old eyes). My Lunt CaK produces a very dim purple image, also with no CaK detail. I know part of the reason is that CaK is shifted toward UV compared to CaH, but the difference in not enough to explain a bright blue sun; that's just a lot of extra light coming through. I sold the Quark CaH and the new owner produced a wonderful image with it. My Lunt also seems to produce nice images.

George

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Re: Different Ca-K options, differences?

Post by krakatoa1883 » Fri Aug 24, 2018 7:50 pm

Actually Quark CaH is advertised for refractors only. I used it with some success with my 130mm solar reflector (dealuminised primary mirror) but I wouldn't recommend it for use with ordinary reflectors (both mirrors aluminised) unless a full aperture front ERF is employed.

Yes, Quark passes more light than an ordinary CaK module, however in my opinion it is an imaging device only. I have been able to see some prominent active regions, i.e. the bright zones around large sunspot groups, but the view was nothing compared to the details that can be imaged with the same device.
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Re: Different Ca-K options, differences?

Post by george9 » Sat Aug 25, 2018 3:23 am

I agree on imaging. I actually got the CaH to test my ability to actually see it. That will have to await a cataract operation. So I switched to the Lunt CaK for quicker startup and hope that the 2A bandpass would be better.

For now I have an R2 video, but will eventually get an ASI of some sort. More for realtime watching than processed images.

George

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Re: Different Ca-K options, differences?

Post by Valery » Sat Aug 25, 2018 2:44 pm

george9 wrote:
Sat Aug 25, 2018 3:23 am
I agree on imaging. I actually got the CaH to test my ability to actually see it. That will have to await a cataract operation. So I switched to the Lunt CaK for quicker startup and hope that the 2A bandpass would be better.

For now I have an R2 video, but will eventually get an ASI of some sort. More for realtime watching than processed images.

George
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Re: Different Ca-K options, differences?

Post by george9 » Thu Aug 30, 2018 7:26 pm

Right, Valery. Thanks. I was very impressed with the realtime image that a NEAF attendee created with his small refractor, Lunt CAK B1200, and ASI174 camera. Not sure what software he was using. Seems like in theory the pixels would be too big for a short-focal-length refractor and I don't remember seeing a Barlow. But I am in no hurry.

George

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