New CaK filter assembly.

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Merlin66
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New CaK filter assembly.

Post by Merlin66 »

Just completing a new CaK 2A filter assembly.....
This version is based on a 2" Baader Blue CCD filter as an "ERF" give a good UV cut below CaK (393nm) and above about 520nm.
Then follows a #1 "Yellow" filter removed from a CaK PST. This has a bandwidth of 2A centred on CaK.
The third element is an Omega 2A CaK filter (as a double stack)

The initial results look promising...
bright speckles showing!

I need to consider whether or not at add a tilter to each or either of the 2A filters to fine tune the CWL.
Used with a stopped down ED80 (60mm f10) and ASI 1600MM.
Firecapture, AS3!, ImPPG, Corono
Onwards and Upwards.
Sun_113525.jpg
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Re: New CaK filter assembly.

Post by marktownley »

Excellent Ken! I use my ED80 stopped down to 60mm regularly for CaK (full disks) and with a 3X barlow for closeups. Maybe use a barlow nosepiece to fill the chip more? Definitely give the DS version a go, looking for the spicule ring is a key that it is working.


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Re: New CaK filter assembly.

Post by Merlin66 »

Some interesting reading on CaK observations (Zirin)
http://adsabs.harvard.edu/full/1974SoPh...38...91Z


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Re: New CaK filter assembly.

Post by allhoest »

It looks promising.
Can you push the system, whilie increasing the resolution, to detect the limit?

CS
Alex


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Re: New CaK filter assembly.

Post by Merlin66 »

Alex,
To be honest the average seeing down here at the coast is pretty poor.
I struggle to use beyond f20 with the Ha, ED80 with x2.5 PM.
I will try the same set up with the CaK.


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